with whom TAMM, Circuit Judge, joins, dissenting:
The question in this case is whether the Fourth Amendment exclusionary rule renders inadmissible, as fruit of the poisonous tree, the .testimony of a live witness whose identity was learned as the result of an illegal search. The majority holds, first, that the exclusionary rule generally applies to cases of live-witness testimony and, second, that the exclusionary rule applies on the facts of this case because the taint affecting the testimony of Thomas Massa, Jr., has not been attenuated, either by that witness’ acts of volition or by other intervening events. I disagree with both conclusions.1
If traditional “attenuation” analysis is applied here, it demonstrates, I believe, that any taint attaching to the testimony of Thomas Massa, Jr., has been dissipated. More fundamentally, however, I believe that traditional “attenuation” analysis is in-apposite in cases of this sort. The question whether live-witness testimony should be suppressed ought to be answered, not by a case-by-case “attenuation” inquiry, but by direct resort to exclusionary rule policies, employing the analysis the Supreme Court has employed in other recent cases involving extensions of the exclusionary rule, such as United States v. Calandra,2 United States v. Janis,3 and Stone v. Powell.4 In those cases the Court adopted a balancing approach under which application of the exclusionary rule in a given class of cases was determined by whether the deterrence benefits of excluding probative evidence justified the social costs of inhibiting the search for truth.
If this balancing approach is applied here, it yields, I believe, a general rule that the exclusionary rule does not operate to exclude the testimony of a live witness whose identity was learned as the result of an illegal search. I conclude, therefore, that Thomas Massa, Jr., should testify, and respectfully dissent.
I. FACTS
It may be useful to begin by detailing somewhat the background to this case, since the majority’s position on the merits has permitted a rather terse and therefore selective recapitulation of the facts. On 15 February 1974 Robert Scios was arrested in New York. In a search incident to that arrest, a file folder was improperly seized by the FBI. Included in the file was a receipt from a motel in Washington, D. C.; attached to this receipt was a piece of paper bearing the name “Mr. Massa.” An FBI agent interviewed the desk manager and the bookkeeper of the motel; neither remembered the occupant of the room. Inquiry revealed, however, that there was still available a record of telephone calls made from the room. There were two numbers, *981one each in New Jersey and New York. Subscribers to these numbers were identified, the one in New York being Thomas Massa. A grand jury subpoena for Thomas Massa was issued. The U. S. Marshal serving the subpoena discovered that there were two Thomas Massas, Senior and Junior, father and son. Contact was made with Thomas Massa, Sr., and other members of the family, but Thomas Massa, Jr. was out of town, unbeatable and unavailable for several days.
When Thomas Massa, Jr., returned to New York, his family told him of the Government’s inquiries and persuaded him that he should speak to the prosecutor. Massa consulted a lawyer in New York, who advised him to say nothing until he was granted immunity. The prosecutor in charge of the investigation refused to offer Massa immunity by letter. On 5 May 1974, therefore, Massa went to Washington and spoke with an Assistant U. S. Attorney. Massa said that he would assert his privilege against self-incrimination before the grand jury. The prosecutor told Massa that a grant of immunity was imminent and asked him for an off-the-record proffer. Massa replied by giving an outline of what his testimony would be. During this meeting Massa was shown some of the Government’s evidence, including material seized from the file folder. Later that same day, Massa claimed his Fifth Amendmént privilege before the grand jury. On 8 May Massa returned to court, having retained counsel in Washington. The district court signed immunity papers, and Massa testified before the grand jury under grant of immunity.
II. TRADITIONAL ATTENUATION ANALYSIS IN LIVE-WITNESS CASES
In Silverthorne Lumber Co. v. United States,5 the Supreme Court held that the exclusionary rule renders inadmissible in a criminal trial not only evidence illegally seized, but evidence collaterally or tangentially derived from an unlawful search or arrest — the “fruit of the poisonous tree.”6 Application of the exclusionary rule to the fruits of lawless activity, of course, has never been absolute. In Silverthorne the Court recognized that facts improperly obtained may be proved at trial “[i]f knowledge of them is gained from an independent source.”7 In Nardone v. United States,8 the Court suggested that arguably tainted evidence may be admitted at trial if the causal connection between that evidence and the Government’s illicit acts has “become so attenuated as to dissipate the taint.”9 It is this “attenuation” doctrine that concerns us here.10
The Supreme Court elaborated the attenuation doctrine in Wong Sun v. United States,11 a case that required the Court to consider whether physical evidence and verbal admissions were fruit of the poisonous tree. In considering whether physical evidence (narcotics) was admissible, the Wong Sun Court said that the proper test was “ ‘whether . . . the evidence to which instant objection is made has been come at by exploitation of [the primary] illegality or instead by means sufficiently distinguishable to be purged of the primary taint.’ ”12 In considering whether verbal admissions were admissible, the Court said that the proper test was whether the statements were “sufficiently an act of free will to *982purge the primary taint.”13 In applying the attenuation doctrine to physical evidence and confessions, in other words, the Court seemed to focus, respectively, on directness of causation and on voluntariness.
The Court descanted on the voluntariness requisite to attenuation in Brown v. Illinois,14 which like Wong Sun involved a confession following an illegal arrest. .The Court said that “[t]he question whether a confession is the product of a free will under Wong Sun must be answered on all the facts of each case;”15 and listed as factors of special relevance the elapsed time between the confession and the arrest, the presence of intervening circumstances, and the flagrancy of the police misconduct.16
These cases did not require the Court to consider whether the exclusionary rule renders inadmissible as fruit of the poisonous tree the testimony of a live witness whose identity was learned as the result of an illegal search.17 The lower courts generally have held such testimony inadmissible, subject to the attenuation doctrine of Wong Sun.18 In gauging attenuation, they have usually employed the same tests used by the Supreme Court to gauge attenuation in the case of physical evidence and confessions. Drawing upon Wong Sun, for example, a number of courts have concluded that the “crucial test” is whether the witness’ testimony constitutes an “exploitation” of the original illegality.19 In answering this question, most courts have hazarded a priori assessments of the “directness” of the causal chain linking the testimony to the primal wrong.20 The courts have considered both *983the amount of time that has elapsed21 and the number of events that have intervened,22 and have been wont to express their analysis in a geographical metaphor: exclusion is required if the road from the illegality to the witness, however long, is not “winding,” but is “uninterrupted” and “straight.”23
Equally prominent in the courts’ analyses has been the inquiry, likewise drawn from Wong Sun, whether the testimony of the live witness is “sufficiently an act of free will to purge the primary taint.”24 In conducting this inquiry, this Court has said that it is necessary to determine in each case “how great a part the particular manifestation of ‘individual human personality’ played in the ultimate receipt of the testimony in question.”25 Indications that a witness’ testimony is sufficiently voluntary include evidence that the witness changed his mind about testifying,26 that the witness would have come forward voluntarily regardless of his identification by the illegal search,27 that uncertainty existed as to the content of the witness’ testimony,28 and that the testimony was not given in response to pressure from the prosecutor or the police.29 In all these cases, the courts *984have agreed that attenuation of a taint affecting live-witness testimony must be determined on an ad hoc basis, after consideration of all the facts of each case.30
If this traditional multi-factor analysis is applied to the facts of this case, it reveals, I believe that any taint attaching to the testimony of Thomas Massa, Jr., has been attenuated. This result follows whether one focuses on the indirectness of the link between that testimony and the primal illegality,31 or on the volitional factors that operated to determine what Massa’s testimony would be.32
Having pondered our experience as revealed in these precedents, however, I have concluded that the traditional analysis should be employed no longer. This fact-oriented, case-by-case approach, which is perpetuated by the majority today, has produced an incoherent and intractable body of law. Whatever the utility of the multi-factor analysis in gauging attenuation of the taint in cases of physical evidence or confessions, that analysis is based on principles which, in the case of live-witness testimony, are of dubious logical relevance. The traditional analysis is bereft of intellectual rigor, for it consists for the most part of bandying conclusory terms that do no more than express the result a court desires to reach. The traditional analysis, not surprisingly, has led to a plethora of inconsistent decisions, not only among the circuits, but within the same circuit.33 I believe that the traditional analysis should be . abandoned and replaced with a balancing approach founded directly on exclusionary rule policies: the proper question is whether the deterrence benefits of excluding live-wit*985ness testimony outweigh the social costs of such exclusion.
III. INADEQUACY OF THE TRADITIONAL ANALYSIS
A. Volition. The most common inquiry in traditional attenuation analysis is whether the witness’ testimony is “sufficiently an act of free will to purge the primary taint.” The threshold objection to this inquiry is the impossibility of determining what, in any given case, in fact causes a witness to testify. In reaching a decision to testify, a witness inevitably operates under a complex of “pressures,” some internally generated (desires to unburden guilt, to gain favor with authority, to be a good citizen), and some externally generated (threats of contempt, grants of immunity, promises of leniency). Psychological and philosophical uncertainties attending the concept of volition ill fit it as a tool of judicial analysis; to say that a statement should be suppressed as insufficiently a product of free will is simply to state the conclusion that the Government’s contribution to the complex of factors producing the testimony is impermissible. Indeed, it was the unmanageability of inquiries into free will that led the Supreme Court to abandon a case-by-case analysis in the coerced-confession cases and embrace a prophylactic rule in Miranda.34
Precisely because the concept of volition is an uncertain tool of judicial analysis, it can be roundly manipulated by the courts. Some courts, for example, have found evidence of a witness’ free will in the fact that he originally resisted testifying, but subsequently changed his mind — as the result, for example, of prosecutorial promises of leniency.35 Other courts have concluded that a witness lacked free will on the basis of the same kind of evidence — pressures or inducements from the prosecution to testify.36 One commentator has accordingly observed that the use of volitional concepts in live-witness eases is “specious and unnecessary, and can be manipulated, whatever the facts or merits of the case, to justify any decision deemed a priori desirable.” 37
Most importantly, inquiry into a witness’ free will is of scant logical relevance in determining whether “attenuation of the taint” has occurred. The courts, I believe, have unthinkingly imported this inquiry from cases like Wong Sun and Brown. Those cases were confession cases, and the confessions were made by the victims of illegal arrests. In order to ascertain whether the confessions were the fruit of illegality, it made sense to inquire whether the confessions were traceable to the lingering effects of improper detention, or whether they sprang from a truly independent source. If the confessions were sufficiently involuntary, in other words, that tended to show that they were the fruit of the poisonous tree. The situation is completely different when live-witness testimony is involved, because the live witness typically will not be the victim of the illegal search or arrest. If the witness’ testimony is “involuntary,” it will not be because the effects of the primal illegality linger and constrain his will, but because he fears prosecution or a contempt citation. Any “compulsion” on Thomas Massa, Jr., evidently, derives not from the taint of the illegal search, but from the judicial immunity order. If live-witness testimony is ever the fruit of the poisonous tree, that determination should be made as of the moment the witness takes the stand; whether he testifies because of an immunity order, a fear of prosecution, or a simple desire to tell the truth is irrelevant in gauging whether the “taint” is attenuated, for the “taint” existed in the distant past and never bore directly upon the witness anyway.
B. Directness of Causation. The second major inquiry in traditional attenuation analysis, likewise derived from Wong Sun, *986is whether the witness’ testimony represents an “exploitation” of the primary illegality. The threshold objection to this formula is its lack of precision. “To exploit” basically means simply “to use,”38 and the police can be said to have exploited the primary illegality in any case where they would not have identified the witness but for the improper search. Yet the Supreme Court has consistently refused to embrace “but for” causality in fruit-of-the-poisonous-tree cases; 39 indeed, “but for” causality would make attenuation impossible. Any attempt to give “exploitation” a narrower sense than “use” reduces it to a pejorative term with no descriptive content; it prohibits the improper use of information without indicating what use is improper.
Efforts to discern “exploitation” by analyzing the “directness” of the casual link between the illegality and the testimony fare no better. Terms like “direct result,” “proximate cause,” and “intervening cause” do not advance analysis: judges in good faith will pick their adjectives according to the result they want to reach. Assessments of the number of “intervening events,” with the implication that the taint becomes more attenuated as the investigation becomes more byzantine, likewise provide a field-day for judicial subjectivity. There is, moreover, little intellectual appeal in a rule which admits or excludes testimony in a criminal trial according to how nearly a police investigation resembles the plot of a cops-and-robbers movie.
The majority’s analysis of this subject, with all respect, is a case in point. The majority finds no attenuation here because “The location of Massa was not the product of an improbable, unforeseeable coincidence. It was good police work, but a straightforward exploration of the leads in the Pharmacy file. . . . ‘The road may be long, but it is straight.’ ”40 Viewed from the vantage point of hindsight, of course, the road in almost every investigation will seem “long but straight” — policemen, for the most part, are rational investigators skilled in inductive science, who are accustomed, for all the majority’s contempt, to explore leads in a “straightforward” manner. Reasoning like the majority’s, which is common in live-witness cases,41 amounts to nothing more than “but for” causality, and would preclude a finding of attenuation in any case.
IV. THE SUPREME COURT’S BALANCING APPROACH
Because of these inadequacies, I believe that traditional attenuation analysis should not be used to ascertain on a case-by-case basis the admissibility of live-witness testimony. Yet the traditional analysis is not only inapposite and impracticable; it is also largely irrelevant to the policies the exclusionary rule is intended to serve. “The basic purpose of the rule,” as Justice Powell said in Brown, “is to remove possible motivations for illegal arrests” and searches.42 In view of this purpose, any rational invocation of the exclusionary rule in live-witness cases must focus on the motivations of the police at the time of the “primary illegality,” for it is this primary illegality that is meant to be deterred. Traditional attenuation analysis, however, focuses not on the motivations of the police at the time of the illegal search or arrest, but on the events intervening after the original misconduct and on the state of mind of the witness at the end of the casual chain.
As a matter of logic, it is hard to see how application of a rule designed to control police behavior can be determined by an analysis that concerns itself exclusively with police behavior and witness motiva*987tions after the fact43 A more rational approach, which concentrates directly on the policies underlying the exclusionary rule and on the motivations of the police at the critical time, has been consistently followed by the Supreme Court in its recent cases.
In these cases, the Court has established beyond peradventure that “the ‘prime purpose’ of the [exclusionary] rule, if not the sole one, ‘is to deter future unlawful police conduct.’ ”44 “By refusing to admit evidence gained as a result of such conduct, the courts hope to instill in those particular investigating officers, or in their future counterparts, a greater degree of care toward the rights of an accused.” 45 The exclusionary rule is not “a personal constitutional right of the party aggrieved,”46 but a judicially-created remedy designed “to compel respect for the constitutional guaranty in the only effectively available way — by removing the incentive to disregard it.”47
“Despite its broad deterrent purpose,” however, “the exclusionary rule has never been interpreted to proscribe the use of illegally seized evidence in all proceedings or against all persons.”48 The Supreme Court has consistently recognized that “the exclusionary rule imposes a substantial cost on the societal interest in law enforcement by its proscription of what concededly is relevant evidence.”49 Application of the *988rule “deflects the truthfinding process and often frees the guilty,”50 and “if applied indiscriminately . . . may well have the . . . effect of generating disrespect for the law and administration of justice.”51 As Justice Powell explained in Stone, “[t]he disparity in particular cases between the error committed by the police officer and the windfall afforded a guilty defendant by application of the rule is contrary to the idea of proportionality that is essential to the concept of justice.” 52
Cognizant both of the deterrence benefits and the social costs of invoking the exclusionary rule, therefore, the Court in its recent cases has adopted a balancing approach. Under this approach, the Court has proceeded “by weighing the utility of the exclusionary rule against the costs of extending it” to a given class of Fourth Amendment claims,53 and has restricted the rule’s application “to those areas where its remedial objectives are thought most efficaciously served.”54 When the rule’s deterrent effect would not be “significantly augmented” 55 and the “additional marginal deterrence” it provides “does not outweigh the cost to society of extending” it;56 when “imposition of the exclusionary rule . is unlikely to provide significant, must less substantial, additional deterrence; ”57 when its “incremental deterrent effect” is “uncertain at best”58 and is outweighed by the “substantial societal costs” of its application,59 the Court consistently has held that the rule does not apply.
In considering whether the exclusionary rule should be extended to cases of live-witness testimony, it is appropriate, I believe, to employ the same balancing approach that the Supreme Court used to consider extensions of the rule in Calandra, Michigan v. Tucker, Janis, and Stone v. Powell.60 Indeed, the Stone Court specifically accommodated the “attenuation of the taint” doc-, trine to the balancing approach it em*989ployed.61 Concurring in Brown, moreover, Justice Powell emphasized that “the Wong Sun [attenuation] inquiry always should be conducted with the deterrent purpose of the . exclusionary rule sharply in focus,” 62 and stated that “[t]he notion of the ‘dissipation of the taint’ attempts to mark the point at which the detrimental consequences of illegal police action become so attenuated that the deterrent effect of the exclusionary rule no longer justifies its cost.”63
V. THE BALANCING APPROACH APPLIED TO LIVE-WITNESS TESTIMONY
Applying the Supreme Court’s balancing approach to this case, the question is whether the deterrence benefits of extending the exclusionary rule to live-witness testimony justify the social costs of deflecting the truthfinding process of the criminal trial. Crucial to this cost/benefit analysis is a careful appreciation of the cognitive and volitional factors that distinguish live-witness testimony from physical evidence. As I have argued above, these cognitive and volitional factors are not relevant to an ex post determination of whether, on the facts of a particular case, the casual chain stemming from the original misconduct is “indirect.” But they are highly relevant to an ex ante determination of whether, as a general rule, the police are likely to be deterred from misconduct by the exclusion of third-party testimony. On balance, I believe that the exclusion of live-witness testimony in general will provide significantly less deterrence and will impose significantly greater social costs than the exclusion of other types of evidentiary fruits.
A. Deterrence Benefits. Any estimate of the deterrence benefits of excluding live-witness testimony must focus on the motivations of the police prior to the “primal illegality.” The extent to which a police officer has an incentive to conduct an illegal search depends, first, on his expectation that the search will uncover useful evidence and, second, on his assessment of the likelihood that what he might discover could be learned in other ways. In both respects, the trial testimony of witnesses differs importantly from physical evidence.
First, owing to the nature of testimonial evidence, the discovery of a potential witness’ name is much less likely than the discovery of tangible objects to eventuate in useful evidence at trial. This is so because tangible evidence generally “speaks for itself,” whereas, as Judge (now Chief Justice) Burger said in Smith & Bowden v. United States,64
[T]he living witness is an individual human personality whose attributes of will, perception, memory and volition interact to determine what testimony he will give. The uniqueness of this human process distinguishes the evidentiary character of a witness from the relative immutability of inanimate evidence.
Police officers, for example, reasonably could expect that if their search uncovers heroin, that evidence (but for the exclusionary rule) could be used effectively against the target of the search. But if they discover the name of someone who might have relevant information, they still face a long list of uncertainties before that name is translated into useful trial testimony. These include, but are not limited to: whether they can locate the individual; whether he will have useful information; whether he will divulge that information; whether he will remain available to testify at the time of trial; whether, if he is unwilling to testify, the prosecutor will be willing to grant him immunity; and whether, if all these uncertainties are favorably resolved, the jury will'find him a credible witness. To these uncertainties must be added the awareness of experienced police *990officers and prosecutors that witnesses often are reluctant to “get involved” in a criminal prosecution by disclosing information or testifying, either because of the inconvenience entailed, a general animus against law enforcement officers, the unpleasant prospect of exposure to hostile cross examination, or the risk of retaliation. In short, it is unlikely that, in the ordinary case, the possibility of finding a useful witness adds significantly to police incentives to conduct an unlawful search, or, conversely, that exclusion of such a witness’ testimony would significantly augment the existing deterrence provided by the exclusion of other types of evidence and its fruits.65
Second, owing to the nature of testimonial evidence, it is almost always significantly more likely that a witness can or will be discovered in the normal course of investigation than that a comparably probative item of tangible evidence can or will be discovered. A witness, unlike tangible evidence, has the capacity to make himself known, and the greater the police expectation that a useful witness exists, the more likely it is that he will come forward. Identification of witnesses, moreover, is a normal subject of any investigation, and witnesses, unlike tangible evidence, can be sought out and interviewed without the necessity of a search — legal or illegal. As a general rule, therefore, the police have significantly less incentive to search for witnesses by unlawful means than to search for other types of evidence by unlawful means.
Although exclusion of live-witness testimony undeniably would provide some “additional marginal deterrence,”66 I conclude, for the reasons given above, that the “incremental deterrent effect ... is uncertain at best.” 67 In most instances of police misconduct, the exclusionary rule will mandate the suppression of tangible evidence, confessions, or both; the rule’s deterrent effect rarely will be “significantly augmented”68 by the exclusion of third-party witness testimony as well.
B. Social Costs. Whatever “incremental deterrent effect” exclusion of live-witness testimony would provide is outweighed by the substantial social costs such exclusion would impose. The Supreme Court has often stressed the deleterious impact of the exclusion of probative evidence on society’s ability to enforce the law.69 In the case of live-witness testimony this impact is especially severe. Tangible evidence and verbal confessions, which speak for themselves, have a finite scope. Exclusion, though critical to the outcome of some cases, thus has a relatively limited impact that in some sense may be deemed “proportionate” to the official wrong.70 To disable a witness and all he may know about a defendant’s prior criminal activities, even though the *991witness’ identity and the knowledge he possesses are totally unrelated both to the purpose of the search and the evidence discovered by the search, would usually impose a cost far out of proportion to the infraction that exclusion is meant to deter.71
The social costs of excluding live-witness testimony, moreover, appear in a particularly stark form, for they are less mitigated by countervailing social benefits from vindicating defendants’ privacy interests. Individuals, of course, have a constitutionally recognized expectation of privacy in their persons, houses, and effects. The introduction of illegally seized evidence frequently will entail a renewed invasion of their privacy.72 Individuals, however, ordinarily have no recognized privacy interest in information disclosed by them to or otherwise possessed by third parties.73 A third party’s testimony at trial, therefore, rarely will trench upon the defendant’s privacy interests, since if it is admissible at all that testimony will concern matters known to the witness wholly independently of any illegal invasion.74
For these reasons, I believe that the social costs of excluding live-witness testimony will almost invariably outweigh the incremental deterrent effect that invocation of the exclusionary rule would produce. This cost/benefit analysis might well come out differently if the police were shown to have acted unlawfully for the specific purpose of discovering potentially useful witnesses.75 Since there is no suggestion of such police motivation in this case, I conclude that the general rule applies, and that Thomas Massa, Jr., should testify.
VI.
On 21 March 1978, shortly before our en banc opinions herein were scheduled to issue, the Supreme Court handed down its decision in United States v. Ceccolini.76 Writing for the Court in that case, Justice Rehnquist held that the testimony of a live witness should not have been suppressed as the fruit of the poisonous tree, notwithstanding that her testimony was the indirect product of an illegal search. This holding was predicated on the Court’s conclusion that “the exclusionary rule should be invoked with much greater reluctance where the claim is based on a causal relationship between a constitutional violation and the discovery of a live witness than when a similar claim is advanced to support *992suppression of an inanimate object.”77 This conclusion obviously strengthens our position that the testimony of Thomas Massa, Jr., should not be suppressed here.
The reasoning we initially followed in our en banc dissent to reach this result rested both on the per se rationale of the Chief Justice’s concurrence and on the traditional attenuation analysis of the Ceccolini majority. Our original, unanimous panel opinion rested only on the latter. Our analysis of the factors producing attenuation of the taint here, as they produced it in Ceccolini, has been removed from the earlier portion of this opinion and rewritten to take the Supreme Court’s latest position into account. But first we refer to the view of the Chief Justice.
In his concurrence the Chief Justice balanced the high cost to society of losing a competent witness “against the prospect of incrementally enhancing Fourth Amendment values,” and concluded that, in general, “the permanent silencing of a witness . is not worth the high price the exclusionary rule exacts.”78 The Chief Justice accordingly advocated a per se approach to the admissibility of live-witness testimony: “such testimony,” he concluded, “is always admissible,” except perhaps in the most unusual circumstances.79 We believe that the Chief Justice’s opinion, particularly its exposition of the perils attending judicial inquiries into witnesses’ voluntariness, is sound, and that it eventually may prove to represent the best and most workable solution to the vexed “tainted witness” problem.
The Ceccolini majority, while echoing the concerns voiced by the Chief Justice, adopted a narrower approach. Rejecting Wong Sun’s suggestion that there is no “logical distinction between physical and verbal evidence,” 80 the majority noted that the social costs of excluding live-witness testimony will generally be greater, and that the deterrence benefits of excluding it will often be less, than in the case of tangible evidence.81 Yet while the majority agreed that a balancing of these costs and benefits “must play a factor in the attenuation analysis,” 82 it declined to hold that this balancing process yielded a per se rule that live-witness testimony is in general admissible. Rather than abandon “traditional attenuation analysis,” the majority determined to accommodate it to “the differences between live-witness testimony and inanimate evidence” 83 by .insisting that the attenuation inquiry be conducted rigorously. “[SJince the cost of excluding live-witness testimony often will be greater,” the Court concluded, “a closer, more direct link between the illegality and that kind of testimony is required.” 84
The approach that the Court adopted in Ceccolini differs significantly from the approach it adopted in Calandra, Janis, and Stone v. Powell. In those cases, the Court balanced the costs and benefits of the exclusionary rule “once and for all” and concluded that the rule generally should not apply in a given class of cases. The Ceccolini majority, by contrast, directed that the balancing should be done on a case-by-case' basis, within the framework of traditional (albeit more rigorous) multifactor attenua*993tion analysis. Justice Rehnquist mentioned five factors arising from the circumstances of that case which pointed to the conclusion that the witness’ testimony should not have been suppressed. These factors' largely overlap the three factors listed by Justice Blackmun as relevant to a finding of attenuation in Brown v. Illinois, a decision that Ceccolini approved.85 Mindful of Justice Rehnquist’s warning that “no mathematical weight can be assigned to any of [these] factors,” and mindful, too, of his injunction that “the exclusionary rule should be invoked with much greater reluctance” in live-witness cases,86 we conclude that, while on the factors specifically cited in Ceccolini this case is arguably closer than that one, certainly in Scios on all the relevant factors sufficient attenuation has occurred to make Massa’s testimony admissible.
Two of the factors mentioned by Justice Rehnquist as pointing to attenuation in Ceccolini are absent from this case.87 More important than their absence, however, is the presence here of the other attenuating factors cited in Ceccolini and Brown v. Illinois: the lapse of a substantial period of time; the presence of significant intervening circumstances; the non-flagrant nature of the original search; and the degree of volition exercised by the witness.
First, as Justice Blackmun in Brown had cited “[t]he temporal proximity of the arrest and the confession”88 as relevant in assessing attenuation, so Justice Rehnquist in Ceccolini adverted to the “[substantial periods of time” that had elapsed between the improper search and the witness’ testimony.89 In the present case, nearly three months passed between the search of the file folder and the Government’s initial contact with Massa. This surely is comparable to the four-month period in Ceccolini. In assessing temporal proximity, moreover, as well as in assessing the second attenuating factor of “intervening circumstances,” it is essential to remember Justice Rehnquist’s clear words: “[A]n examination of our cases persuades us that the Court of Appeals was simply wrong in concluding that if. the road were uninterrupted, its length was immaterial. Its length, we hold, is material . . ..”90
Second, the Court in Brown cited “the presence of intervening circumstances” as a relevant factor in determining attenuation. In this case, the following events intervened between the FBI’s search and Massa’s testimony before the grand jury: (1) the FBI unsuccessfully contacted the motel desk clerk and bookkeeper; (2) the FBI discovered a list of telephone calls made from the motel room; (3) subscribers to the phones were identified, including Thomas Massa; (4) the FBI contacted Massa’s family, and learned that Thomas Massa, Jr., in whom they were interested, was not available; (5) Massa consulted his family and his lawyer; (6) Massa went to Washington, spoke to a U. S. Attorney, and made an off-the-record proffer; (7) Massa consulted a Washington lawyer; (8) the court entered an order granting Massa immunity from prosecution.
Perhaps the most important “intervening event” is the last, which establishes a close nexus between this case and Justice White’s *994opinion in Johnson v. Louisiana.91 In Johnson appellant claimed that his identification in a line-up should be excluded as the fruit of an illegal arrest. The Court rejected this argument. It pointed out that prior to the line-up Johnson had been brought before a committing magistrate to advise him of his rights and set bail. Consequently, at the time of the line-up, Johnson’s detention was under the authority of this commitment, and the line-up was conducted not by exploitation of the challenged arrest but “ ‘by means sufficiently distinguishable to be purged of the primary taint.’ ”92 Similarly, when Massa testified before the grand jury under a grant of immunity, he was testifying under the authority of the immunity papers signed by the district judge. His testimony was thus not an exploitation of the illegal search but the product of the immunity order, a means “sufficiently distinguishable to be purged of the primary taint.” The relevance of Johnson to this case is established beyond peradventure by Brown v. Illinois. In citing “the presence of intervening circumstances” as one factor relevant to finding of attenuation, Brown cited Johnson93
A third factor, described in Brown as of particular relevance in gauging attenuation, is “the purpose and flagrancy of the official misconduct.” 94 In Ceccolini, similarly, the Court concluded that application of the exclusionary rule “could not have the slightest deterrent effect” because there was no evidence to suggest that the officer made the search “with the intent of finding [useful] tangible evidence . . ., much less any suggestion that he entered the shop and searched with the intent of finding a willing and knowledgeable witness. .”95 In the present case, the FBI agents undeniably searched with the intent of finding evidence (or weapons) relevant to their investigation of Scios, since they purportedly made their search as incident to his arrest. But there is no suggestion here, as there was none Ceccolini, that the officers searched with the intent of discovering witnesses. It seems unlikely, therefore, that suppression of Massa’s testimony would enhance the deterrence already flowing from the exclusion of the tangible evidence and its fruits.
Of even greater importance in this case, given Brown, is the non-flagrant nature of the original search. “The deterrent purpose of the exclusionary rule,” Justice Rehnquist wrote in Michigan v. Tucker, “necessarily assumes that the police have engaged in willful, or at the very least negligent, conduct which has deprived the defendant of some right.”96 “In cases in which this underlying premise is lacking,” Justice Powell wrote concurring in Brown, “the deterrence rationale of the exclusionary rule does not obtain, and [there is] no legitimate justification for depriving the prosecution of reliable and probative evidence.” 97 The behavior of the FBI agents in this case was hardly egregious. When they arrested Scios, they seized a file folder from the top of a credenza a few feet behind him. It seems undisputed that the file folder was within the “grabbing distance” defined by the Supreme Court in Chimel v. California98 as the spatial limit to a valid search incident to arrest. The search would thus have been perfectly proper, were it not for the fortuity that an agent happened to be standing between Scios and the credenza. The folder, surely, *995was something a reasonable officer in good faith could have thought he had a right to seize. Indeed, as one of the agents admitted, they were unsure if they could properly seize the file folder and did so only after discussing the matter among themselves.99 This evidently was what Justice Powell has called a “technical” violation of the Fourth Amendment,100 and is a case in which invocation of the exclusionary rule is unlikely to serve any deterrent purpose whatsoever.
Nor can it be argued that the agents’ good faith can be attributed only to “ignorance of the law.” The agents, obviously, were chargeable with knowledge of the Chime] rule; the point is that there was room for argument as to whether the Chime! rule interdicted a search on the facts of this case. Uncertainty as to the law’s fine lines, surely, is a plague that undoubtedly besets many law enforcement officers — a result that is not surprising in view of the tortured path our search-and-seizure law has followed. The FBI agents here treated Scios throughout with courtesy; they conducted no general search; and before seizing the file folder they had the presence of mind to discuss the propriety of the seizure in calm and reasoned terms. The agents, in short, behaved very much as we should like law enforcement officers to behave. Their behavior was in no sense egregious, and their decision to seize the folder, while not the decision some courts would have reached, was plainly not reached thoughtlessly or in bad faith. My point is simply that in these circumstances the exclusionary rule is of scant deterrent value — and this simple point is what this and other attenuation cases are all about.
A fourth factor, common in traditional attenuation analysis and central to Brown, is the degree to which verbal evidence represents the uncoerced product of the speaker’s will. The majority in Ceccolini likewise concluded that “the degree of free will exercised by the witness is not irrelevant in determining the extent to which the basic purpose of the exclusionary rule will be advanced by its application,”101 and held the testimony admissible in part because it was demonstrably “an act of [the witness’] own free will in no way coerced or even induced by official authority . . ..”102 The testimony at issue in this case, I believe, was quite clearly voluntary. The record reveals at least four clear-cut acts of volition on Massa’s part: (1) he consulted his family, who tried to persuade him to speak with the prosecutor; (2) he consulted his lawyer, who advised him to say nothing without a grant of immunity; (3) he went to Washington and made an off-the-record proffer of his proposed testimony after being told that a grant of immunity was imminent; (4) he retained new counsel and testified under the immunity order. The totality of these circumstances shows a reflective man seeking advice, pondering in advance the consequences of his action and the testimony he would give, qxercising his free will in giving the prosecutor certain information, and finally testifying, on the advice of his lawyer, with judicial immunity. Massa changed his mind about testifying, it is true, but this very circumstance has consistently been cited by the courts as evidence of voluntariness sufficient to cause attenuation.103 At least one other court, moreover, has cited a witness’ consultation of his lawyer as evidence of volition leading to a finding of attenuation.104
*996The majority argues that it is more difficult to show attenuation here than in Ceccolini because “official authority” may here be said to have induced Massa to testify. But the majority is simply wrong in saying that the judicial immunity order rendered Massa’s testimony “purely and simply a product of coercion.”105 The Fifth Circuit recently has held (in a pre-Ceccolini case) that a witness’ testimony was voluntary, and hence that any taint affecting it had become attenuated, where the witness testified under a grant of use immunity.106 A number of courts have held that testimony was the product of a witness’ free will, with a consequent finding of attenuation, where the witness testified in response to a promise of leniency or non-prosecution.107 Courts almost unanimously have found testimony of accessories “sufficiently a product of free will” to cause attenuation; although the opinions do not state what promises were made to these witnesses, it seems likely that they testified in response to some prosecutorial inducements.108 The immunity order in this case undoubtedly offered Massa an inducement to testify. But it did not therefore coerce him: it was but one factor in his cost/benefit analysis, one event in the long chain of volitional events that produced the testimony he ultimately gave. And whatever the impact of the immunity order in Massa’s thinking, it cannot be doubted that here, at least, in Ceccolini’s words “the illegality which led to the discovery of the witness [did] not play any meaningful part in [his] willingness to testify.”109
From my discussion of these four attenuating factors, it is obvious that I do not regard Scios and Ceccolini as fitting hand in glove. Several of the factors pointing to Justice Rehnquist’s conclusion are absent, or are present in less convincing guise, here. Yet the Court cautioned against assigning the factors it discussed any “mathematical weight,” and precisely because Ceccolini was an easy case, subsequent eases cannot be expected to be decided within its facts. Nor, indeed, can we expect to decide many of these live-witness attenuation cases within the facts of previous decisions. The combination of circumstances has already proved to be infinite, so much so that the Supreme Court’s enumeration of relevant factors as guidelines in assessing attenuation on a case-by-case basis shows such variance (compare Justice Blackmun in Brown with Justice Rehnquist in Ceccolini, the factors cited as relevant obviously being inspired by the case at hand). This lends weight to the Chief Justice’s sponsorship of a per se rule in all but the most unusual live-witness cases. But since the Supreme Court majority has held that attenuation should be examined on a case-by-case basis, and analyzed with reference to factors relevant in each particular case, analysis of the circumstances of Massa’s live testimony in Scios’ case persuades me that, on all the precedents, there has been attenuation of *997any possible taint. There is no justification for suppression. The course of justice calls for the witness to be heard. I therefore must respectfully dissent.
. The bulk of this opinion was written prior to United States v. Ceccolini, 435 U.S. 268, 98 S.Ct. 1054, 55 L.Ed.2d 268 (1978), in which the Supreme Court for the first time considered whether the exclusionary rule requires suppression of the testimony of a witness whose identity or whose possession of relevant information was learned as the result of án illegal search. The Ceccolini majority, while holding that sufficient attenuation had occurred on the facts of that case to make the testimony in question admissible, declined to embrace the principle, advocated by the Justice Department, adopted by the Chief Justice, and recommended here, that the exclusionary rule in general should not apply to live-witness testimony. • The multi-factor attenuation analysis employed by the Ceccolini majority is applied to the facts of this case in Part VI infra.
. 414 U.S. 338, 94 S.Ct. 613, 38 L.Ed.2d 561 (1974) (exclusionary rule does not operate in grand jury proceeding to bar questions based on evidence obtained from unlawful search and seizure).
. 428 U.S. 433, 96 S.Ct. 3021, 49 L.Ed.2d 1046 (1976) (exclusionary rule does not operate in federal civil proceeding to bar evidence unlawfully seized by state criminal authorities).
. 428 U.S. 465, 96 S.Ct. 3037, 49 L.Ed.2d 1067 (1976) (state prisoner cannot raise exclusionary rule claim on federal habeas corpus when he has been afforded opportunity for full and fair litigation of claim in state courts).
. 251 U.S. 385, 392, 40 S.Ct. 182, 64 L.Ed. 319 (1920).
. See Nardone v. United States, 308 U.S. 338, 341, 60 S.Ct. 266, 84 L.Ed. 307 (1939).
. 251 U.S. at 392, 40 S.Ct. at 183.
. 308 U.S. 338, 60 S.Ct. 266, 84 L.Ed. 307 (1939).
. Id. at 341, 60 S.Ct. at 268.
. In' neither this Court nor the district court did the Government contend that there was an independent source for Massa’s testimony. See Brief of the United States at 12.
. 371 U.S. 471, 83 S.Ct. 407, 9 L.Ed.2d 441 (1963).
. Id. at 488, 83 S.Ct. at 417, quoting Maguire, Evidence of Guilt 221 (1959) (emphasis added).
. Id. at 486, 83 S.Ct. at 416 (footnote omitted, emphasis added). Defendant Toy had made incriminating statements in his bedroom following a 6 a. m. police raid. “Under such circumstances,” said the Court, “it is unreasonable to infer that Toy’s response was sufficiently an act of free will to purge the primary taint of the unlawful invasion.” Id. Defendant Wong Sun had made incriminating statements at the police station after he “had been released on his own recognizance . . . and had returned voluntarily several days later” to confess. On this evidence, the Court had that “the connection between the [illegal] arrest and the statement had ‘become so attenuated as to dissipate the taint.’ ” Id. at 491, 83 S.Ct. at 419, quoting Nardone, 308 U.S. at 341, 60 S.Ct. 266.
. 422 U.S. 590, 95 S.Ct. 2254, 45 L.Ed.2d 416 (1975).
. Id. at 603, 95 S.Ct. at 2261.
. Id. at 603-04, 95 S.Ct. 2254. Fifth Amendment voluntariness, said the Court, is merely a “threshold requirement.” Id. at 604, 95 S.Ct. 2254.
. The Court did not consider this question until United States v. Ceccolini, 435 U.S. 268, 98 S.Ct. 1054, 55 L.Ed.2d 268 (1978). See United States v. Brignoni-Ponce, 422 U.S. 873, 876 n.2, 95 S.Ct. 2574, 2577, 45 L.Ed.2d 607 (1975) (“There may be room to question whether voluntary testimony of a witness at trial . . . is subject to suppression as the fruit of an illegal search or seizure. . . . But since the question was not raised in the petition for certiorari, we do not address it.”); Harrison v. United States, 392 U.S. 219, 223 n.9, 88 S.Ct. 2008, 2010, 20 L.Ed.2d 1047 (1968) (“We have no occasion in this case to canvass the complex and varied problems that arise when the trial testimony of a witness other than the accused is challenged as ‘the evidentiary product of the poisoned tree’ ”) (quoting Ruffin, Out on a Limb of the Poisonous Tree: The Tainted Witness, 15 U.C.L.A.L.Rev. 32, 44 (1967)).
. E. g., United States v. Ceccolini, 542 F.2d 136, 142 (2d Cir. 1976), rev’d, 435 U.S. 268, 98 S.Ct. 1054, 55 L.Ed.2d 268 (1978); United States v. Guana-Sanchez, 484 F.2d 590, 592 (7th Cir. 1973), cert. dismissed as improvidently granted, 420 U.S. 513, 95 S.Ct. 1344, 43 L.Ed.2d 361 (1975); United States v. Marder, 474 F.2d 1192, 1195 (5th Cir. 1973) (“This circuit has followed the general rule that if the identity of a government witness and his relationship to the defendant are revealed because of an illegal search and seizure, the testimony of such witness must be excluded”) (citing cases); Smith and Anderson v. United States, 120 U.S.App.D.C. 160, 162, 344 F.2d 545, 547 (1965).
. United States v. Beasley, 485 F.2d 60, 64 (10th Cir. 1973), cert. denied, 416 U.S. 941, 94 S.Ct. 1946, 40 L.Ed.2d 292 (1974). See United States v. Hoffman, 385 F.2d 501, 504 (7th Cir. 1967), cert. denied, 390 U.S. 1031, 88 S.Ct. 1424, 20 L.Ed.2d 288 (1968); Smith and Anderson v. United States, 120 U.S.App.D.C. 160, 162, 344 F.2d 545, 547 (1965); Edwards v. United States, 117 U.S.App.D.C. 383, 385, 330 F.2d 849, 851 (1964).
. E. g., United States v. Karanthos, 531 F.2d 26, 35 (2d Cir.), cert. denied, 428 U.S. 910, 96 S.Ct. 3221, 49 L.Ed.2d 1217 (1976) (“close connection” between illegal search and live-witness testimony). Compare, Parker v. Estelle, *983498 F.2d 625, 630 (5th Cir. 1974), cert. denied, 421 U.S. 963, 95 S.Ct. 1951, 44 L.Ed.2d 450 (1975) (live-witness testimony admissible unless tied “clearly and directly” to illegal search) with Williams v. United States, 382 F.2d 48, 51 (5th Cir. 1967) (live-witness testimony inadmissible if “indirect product” of illegal search) and United States v. Tane, 329 F.2d 848, 853 (2d Cir. 1964) (live-witness testimony inadmissible if illegal information led “directly or indirectly” to discovery of witness).
. E. g., United States v. Beasley, 485 F.2d 60, 64 (10th Cir. 1973), cert. denied, 416 U.S. 941, 94 S.Ct. 1946, 40 L.Ed.2d 292 (1974) (lapse of three days between illegal event and witness’ decision to testify causes attenuation); Brown v. United States, 126 U.S.App.D.C. 134, 138, 375 F.2d 310, 314, cert. denied, 388 U.S. 915, 87 S.Ct. 2133, 18 L.Ed.2d 1359 (1967) (lapse of 13 months between illegal event and witness’ testimony causes attenuation).
. E. g., United States v. Evans, 454 F.2d 813, 818 (8th Cir.), cert. denied, 406 U.S. 969, 92 S.Ct. 2423, 32 L.Ed.2d 668 (1972); Brown v. United States, 126 U.S.App.D.C. 134, 138, 375 F.2d 310, 314, cert. denied, 388 U.S. 915, 87 S.Ct. 2133, 18 L.Ed.2d 1359 (1967).
. E. g., United States v. Ceccolini, 542 F.2d 136, 142 (2d Cir. 1976), rev’d, 435 U.S. 268, 98 S.Ct. 1054, 55 L.Ed.2d 268 (1978) (road from unconstitutional search to witness’ testimony “is both straight and uninterrupted”); Williams v. United States, 382 F.2d 48, 51 (5th Cir. 1967) (“road from the illegal search to the testimony . . . although a little long, was not a winding one”); Smith and Anderson v. United States, 120 U.S.App.D.C. 160, 162, 344 F.2d 545, 547 (D.C.Cir. 1965), quoting United States v. Tane, 329 F.2d 848, 853 (2d Cir. 1964) (“The road from the [illegal source] to the testimony may be long, but it is straight”).
. E. g., United States v. Karanthos, 531 F.2d 26, 35 (2d Cir.), cert. denied, 428 U.S. 910, 96 S.Ct. 3221, 49 L.Ed.2d 1217 (1976) (testimony inadmissible where witnesses were subject to Government “leverage”); United States v. Crouch, 528 F.2d 625, 629-30 (7th Cir.), cert. denied, 429 U.S. 900, 97 S.Ct. 266, 50 L.Ed.2d 184 (1976) (testimony admissible where witness “made a voluntary choice to divulge . information”); United States v. Beasley, 485 F.2d 60, 64 (10th Cir. 1973), cert. denied, 416 U.S. 941, 94 S.Ct. 1946, 40 L.Ed.2d 292 (1974) (testimony admissible where there was “high degree of probability that [witness] exercised her own volition”); United States v. Hoffman, 385 F.2d 501, 504 (7th Cir. 1967), cert. denied, 390 U.S. 1031, 88 S.Ct. 1424, 20 L.Ed.2d 288 (1968) (testimony admissible where witness made “voluntary decision to plead guilty” and testify for prosecution); United States v. Tane, 329 F.2d 848, 853 (2d Cir. 1964) (testimony inadmissible where witness was unwilling to testify until informed that police had information gained from illegal wiretap).
. McLindon v. United States, 117 U.S.App.D.C. 283, 286, 329 F.2d 238, 241 n.2 (1964).
. See United States v. Marder, 474 F.2d 1192, 1196 (5th Cir. 1973); Edwards v. United States, 117 U.S.App.D.C. 383, 385, 386, 330 F.2d 849, 851-52 (1964); McLindon v. United States, 117 U.S.App.D.C. 283, 286, 329 F.2d 238, 241 n.2 (1964).
. See United States v. Marder, 474 F.2d 1192, 1196 (5th Cir. 1973); McLindon v. United States, 117 U.S.App.D.C. 283, 286, 329 F.2d 238, 241 n.2 (1964).
. Id.
. Compare United States v. Karanthos, 531 F.2d 26, 35 (2d Cir.), cert. denied, 428 U.S. 910, 96 S.Ct. 3221, 49 L.Ed.2d 1217 (1976) (testimony inadmissible where witnesses agreed to testify after promise of non-prosecution) and Unit*984ed States v. Tane, 329 F.2d 848, 853 (2d Cir. 1964) (testimony inadmissible where witness agreed to testify only after police revealed knowledge of facts gained from illegal tap) with Brown v. United States, 126 U.S.App.D.C. 134, 139, 375 F.2d 310, 315, cert. denied, 388 U.S. 915, 87 S.Ct. 2133, 18 L.Ed.2d 1359 (1967) (testimony admissible despite strong evidence that witness agreed to testify after promise of non-prosecution). But see notes 108-09 infra.
. See United States v. Marder, 474 F.2d 1192, 1196 (5th Cir. 1973); United States v. Evans, 454 F.2d 813, 818 (8th Cir.), cert. denied, 406 U.S. 969, 92 S.Ct. 2423, 32 L.Ed.2d 668 (1972); Williams v. United States, 382 F.2d 48, 51 (5th Cir. 1967); McLindon v. United States, 117 U.S.App.D.C. 283, 286, 329 F.2d 238, 241 n.2 (1964).
. See pp.---of 191 U.S.App.D.C., pp. 993-994 of 590 F.2d infra.
. See pp.---of 191 U.S.App.D.C., pp. 995-997 of 590 F.2d infra.
. Several courts have commented on the disparate judicial approaches to the exclusion of live-witness testimony. E. g., United States v. Ceccolini, 542 F.2d 136, 144 n.3 (2d Cir. 1976) (Van Graafeiland, J., dissenting); United States v. Evans, 454 F.2d 813, 818 (8th Cir.), cert. denied, 406 U.S. 969, 92 S.Ct. 2423, 32 L.Ed.2d 668 (1972).
Intra-circuit conflict is perhaps most evident in this Court, the results ranging from the views of the present Chief Justice Burger to those of former Chief Judge Bazelon. In Smith and Bowden v. United States, 117 U.S.App.D.C. 1, 324 F.2d 879 (1963), cert. denied, 377 U.S. 954, 84 S.Ct. 1632, 12 L.Ed.2d 498 (1964), Judge Burger propounded what amounted to a per se rule of attenuation in live-witness cases. See id. at 3, 4, 324 F.2d at 881, 882; id. at 6, 324 F.2d at 884 n.6 (Bazelon, C. J., dissenting) (“The majority would except the oral testimony of a ‘living witness’ from the ‘fruit of the poisoned tree’ doctrine, on the ground that a witness is an ‘individual human personality’ possessing ‘attributes of will, perception, memory and volition.’ ”); Brown v. United States, 126 U.S.App.D.C. 134, 139, 375 F.2d 310, 319, cert. denied, 388 U.S. 915, 87 S.Ct. 2133, 18 L.Ed.2d 1359 (1967) (Burger, J., concurring) (“The critical aspect of Smith-Bowden is that live witnesses are not ‘suppressed,’ as inanimate objects may be. When an eyewitness is willing to give testimony, ... he must be heard.”) Subsequently, however, a different panel of this Court promulgated a “multiple factors,” case-by-case approach. See McLindon v. United States, 117 U.S.App.D.C. 283, 286, 329 F.2d 238, 241 n.2 (1964), cited in notes 27-30 supra; Edwards v. United States, 117 U.S.App.D.C. 383, 385-386, 330 F.2d 849, 851-52 (1964) (apparently following McLindon). In Smith and Anderson v. United States, 120 U.S.App.D.C. 160, 344 F.2d 545 (1965), a third panel of this Court paid lip-service to the McLindon approach, while pronouncing what amounted to a rule of “but-for” causality. See id. at 162, 344 F.2d at 547 (Bazelon, C. J.) (live-witness testimony inadmissible, despite intervention of “several ‘human personalities,’ ” because police “used” knowledge improperly obtained and witness would not have come forward “were it not for” police investigation).
. Miranda v. Arizona, 384 U.S. 436, 86 S.Ct. 1602, 16 L.Ed.2d 694 (1966).
. See notes 108-09 infra.
. See note 29 supra.
. Ruffin, Out on a Limb of the Poisonous Tree: The Tainted Witness, 15 U.C.L.A.L.Rev. 32, 64 (1967).
. See Webster’s New Collegiate Dictionary 404 (1973).
. See Brown v. Illinois, 422 U.S. 590, 603, 95 S.Ct. 2254, 45 L.Ed.2d 416 (1975); Wong Sun v. United States, 371 U.S. 471, 487-88, 83 S.Ct. 407, 9 L.Ed.2d 441 (1963).
. Maj. op. at - of 191 U.S.App.D.C., at 961 of 590 F.2d, quoting United States v. Tane, 329 F.2d 848, 853 (2d Cir. 1964).
. See note 23 supra.
. 422 U.S. at 610, 95 S.Ct. at 2265 (Powell, J„ concurring in part).
. See United States v. Guana-Sanchez, 484 F.2d 590, 594 (7th Cir. 1973), cert. dismissed as improvidentiy granted, 420 U.S. 513, 95 S.Ct. 1344, 43 L.Ed.2d 361 (1975) (Pell, J., dissenting):
I have some conceptual difficulty in determining how an exclusionary rule designed to control police behavior can be applied on a case-by-case basis as Smith [and Anderson v. United States, cited in note 33 supra ] would have us do. I am certain that police officers would have an even greater difficulty in determining whether a possible witness’s testimony was attenuated from illegality.
. United States v. Janis, 428 U.S. 433, 446, 96 S.Ct. 3021, 3028, 49 L.Ed.2d 1046 (1976), quoting United States v. Calandra, 414 U.S. 338, 347, 94 S.Ct. 613, 38 L.Ed.2d 561 (1974). Accord, Stone v. Powell, 428 U.S. 465, 486, 96 S.Ct. 3037, 3048, 49 L.Ed.2d 1067 (1976) (“The primary justification for the exclusionary rule . . . is the deterrence of police conduct that violates Fourth Amendment rights.”) (cit-, ing cases). The Court occasionally has mentioned, as an alternative rationale for the exclusionary rule, “the imperative of judicial integrity.” E. g., United States v. Peltier, 422 U.S. 531, 536-39, 95 S.Ct. 2313, 45 L.Ed.2d 374 (1975); Elkins v. United States, 364 U.S. 206, 222, 80 S.Ct. 1437, 4 L.Ed.2d 1669 (1960). In the Court’s more recent decisions, however, the “judicial integrity” rationale has been almost completely discarded. Taken to its logical extension, as Justice Powell pointed out in Stone, the “judicial integrity” rationale would dictate reversal of the Court’s well-established doctrines on standing to object to admission of illegally-seized evidence, impeachment use of such evidence, and admissibility of such evidence absent objection by defendant. See 428 U.S. at 485, 96 S.Ct. 3037 (citing cases). Justice Blackmun pointed out in Janis that the “judicial integrity” inquiry in Fourth Amendment cases “is essentially the same as the inquiry into whether exclusion would serve a deterrent purpose,” 428 U.S. at 458-59 n.35, 96 S.Ct. at 3034; and Justice Rehnquist noted in Michigan v. Tucker that the “judicial integrity” rationale “is really an assimilation of the more specific rationales” such as deterrence, “and does not in their absence provide an independent basis for excluding challenged evidence.” 417 U.S. at 450 n.25, 94 S.Ct. at 2367. Concern with judicial integrity, in sum, “has limited force as a justification for the exclusion of highly probative evidence.” Stone, 428 U.S. at 485, 96 S.Ct. at 3048 (footnote omitted).
. Michigan v. Tucker, 417 U.S. 433, 447, 94 S.Ct. 2357, 2365, 41 L.Ed.2d 182 (1974).
. United States v. Calandra, 414 U.S. 338, 348, 94 S.Ct. 613, 620, 38 L.Ed.2d 561 (1974) (footnote omitted).
. Id. at 347, 94 S.Ct. at 620, quoting Elkins v. United States, 364 U.S. 206, 217, 80 S.Ct. 1457, 4 L.Ed.2d 1669 (1960). Whether the exclusionary rule is indeed “the only effectively available way” to deal with unconstitutional searches and seizures, of course, has become a matter of considerable doubt. The Court recently has acknowledged that the deterrent effect of the exclusionary rule is more an assumed hypothesis than a demonstrable fact. See Stone v. Powell, 428 U.S. at 492 & n.32, 96 S.Ct. 3037; United States v. Janis, 428 U.S. at 450-52 n.22, 96 S.Ct. 3021; United States v. Calandra, 414 U.S. at 348 n.5, 94 S.Ct. 613.
. Id. at 348, 94 S.Ct. at 620. See Stone v. Powell, 428 U.S. at 486-87, 96 S.Ct. 3037.
. United States v. Janis, 428 U.S. at 448-49, 96 S.Ct. at 3029. Accord, Michigan v. Tucker, 417 U.S. at 450, 94 S.Ct. 2357. The Court recognized the societal costs imposed by the exclusionary rule as early as Nardone:
*988Any claim for the exclusion of evidence logically relevant in criminal prosecutions is heavily handicapped. It must be justified by an over-riding public policy expressed in the Constitution or the law of the land.
308 U.S. 338, 340, 60 S.Ct. 266, 267, 84 L.Ed. 307 (1939).
. Stone v. Powell, 428 U.S. at 490, 96 S.Ct. at 3050.
. Id. at 491, 96 S.Ct. at 3051 (footnote omitted).
. Id. at 490, 96 S.Ct. at 3050 (footnote omitted).
. Id. at 489, 96 S.Ct. at 3050.
. Id. at 486-87, 96 S.Ct. at 3049, citing United States v. Calandra, 414 U.S. at 348, 94 S.Ct. 613.
. Michigan v. Tucker, 417 U.S. at 448, 94 S.Ct. 2357.
. United States v. Janis, 428 U.S. at 453-54, 96 S.Ct. at 3032.
. Id. at 458, 96 S.Ct. at 3034.
. United States v. Calandra, 414 U.S. at 351, 94 S.Ct. 613.
. Stone v. Powell, 428 U.S. at 495, 96 S.Ct. 3037.
. Several circuit courts have adopted a balancing approach in live-witness cases. In Smith and Bowden v. United States, 117 U.S.App.D.C. 1, 324 F.2d 879 (1963), cert. denied, 377 U.S. 954, 84 S.Ct. 1632, 12 L.Ed.2d 498 (1964), Judge (now Chief Justice) Burger fo-' cused on the unique nature of live-witness testimony and concluded that in general there was “no rational basis” for excluding the testimony of an eyewitness to a crime. See note 33 supra. Judge Clark used a balancing approach in Parker v. Estelle. See 498 F.2d 625, 630 (5th Cir. 1974), cert. denied, 421 U.S. 963, 95 S.Ct. 1951, 44 L.Ed.2d 450 (1975) (“[W]e do not think it would serve the deterrent purpose of the exclusionary rule to deny to [defendant’s] trial not merely the unlawful confession, but also truthful testimony from [a third-party witness]”). Judge Pell, dissenting in United States v. Guana-Sanchez, did the same. See 484 F.2d 590, 593 (7th Cir. 1973), cert. dismissed as improvidently granted, 420 U.S. 513, 95 S.Ct. 1344, 43 L.Ed.2d 361 (1975) (“[T]he rationale of the exclusionary rule . does not call for its extension to the point of excluding altogether an otherwise competent witness”). Cf. United States v. Paepke, 550 F.2d 385, 388-91 (7th Cir. 1977) (balancing deterrence benefits of exclusionary rule against risk of injury to tax-collection system and concluding that exclusionary rule does not prohibit use of illegally seized evidence in criminal prosecution for tax fraud committed after search) (citing Scios panel opinion).
. See 428 U.S. at 489 n.26, 96 S.Ct. 3037.
. 422 U.S. at 612, 95 S.Ct. at 2266 (Powell, J., concurring in part).
. Id. at 609, 95 S.Ct. at 2264.
. 117 U.S.App.D.C. 1, 3—4, 324 F.2d 879, 881-82 (1963), cert. denied, 377 U.S. 954, 84 S.Ct. 1632, 12 L.Ed.2d 498 (1964) (footnotes omitted).
. There are two extraordinary types of cases in which exclusion of a witness’ testimony is necessary to deter police misconduct. The first is where the police engage in unlawful acts for the specific purpose of discovering potentially useful witnesses. See p. - of 191 U.S.App.D.C., p. 991 of 590 F.2d infra. The second is where the witness’ testimony (e. g., the testimony of a police officer who participated in an illegal search) describes illegally seized evidence or otherwise inadmissible fruits. The deterrence principle obviously would be emasculated if the prosecution could use a willing witness to describe tainted evidence, and under established exclusionary rule doctrine such testimony is inadmissible. My analysis and conclusions are confined to the ordinary cases of live-witness testimony — the types of cases with which the circuit court opinions cited above have uniformly been concerned — in which the witness’ testimony derives from knowledge he possesses independently of any illegal police conduct.
. United States v. Janis, 428 U.S. at 453, 96 S.Ct. 3021.
. United States v. Calandra, 414 U.S. at 351, 94 S.Ct. at 621.
. Michigan v. Tucker, 417 U.S. at 448, 94 S.Ct. 2357.
. See pp.--- of 191 U.S.App.D.C., pp. 987-988 of 590 F.2d supra.
. In Stone, Justice Powell stressed the important role played by proportionality in criminal justice. See 428 U.S. at 490-91 & n. 29, 96 S.Ct. 3037, quoted at p. - of 191 U.S.App. D.C., p. 988 of 590 F.2d supra.
. The path of the law, of course, has headed unerringly toward unrestricted admission of relevant testimony. See McCormick’s Evidence § 71 at 150 (2d ed. E. Cleary 1972):
The rules which disqualify witnesses who have knowledge of relevant facts and mental capacity to convey that knowledge are serious obstructions to the ascertainment of truth. For a century the course of legal evolution has been in the direction of sweeping away these obstructions.
See Brown v. United States, 126 U.S.App.D.C. 134, 143, 375 F.2d 310, 319, cert. denied, 388 U.S. 915, 87 S.Ct. 2133, 18 L.Ed.2d 1359 (1967) (Burger, J., concurring), quoted in note 33 supra.
. It is on this principle, for example, that 18 U.S.C. §§ 2510-2520 (1976), regulating electronic surveillance, prohibit not only unauthorized interception of communications but equally their subsequent disclosure.
. See, e. g., United States v. Miller, 425 U.S. 435, 96 S.Ct. 1619, 48 L.Ed.2d 71 (1976) (depositor has no Fourth Amendment interest in bank records relating to his accounts); Couch v. United States, 409 U.S. 322, 93 S.Ct. 611, 34 L.Ed.2d 548 (1973) (taxpayer has no Fourth or Fifth Amendment interest in financial records surrendered to accountant); United States v. White, 401 U.S. 745, 91 S.Ct. 1122, 28 L.Ed.2d 453 (1971) (defendant has no Fourth Amendment interest in statements overheard by informer who was “wired for sound”).
. Testimony concerning matters known to a witness by virtue of illegal police activity, such as testimony describing objects illegally seized, is inadmissible. See note 65 supra.
. Such a case is probably illustrated by United States v. Karanthos, 531 F.2d 26 (2d Cir.), cert. denied, 428 U.S. 910, 96 S.Ct. 3221, 49 L.Ed.2d 1217 (1976). An affidavit supporting the search warrant in that case revealed that federal agents searched a restaurant for the specific purpose of discovering illegal aliens, id. at 28-29; the Government subsequently sought to use the aliens’ testimony against the restaurant owner.
. 435 U.S. 268, 98 S.Ct. 1054, 55 L.Ed.2d 268 (1978). '
. Id. at 280, 98 S.Ct. at 1062, 55 L.Ed.2d at 279.
. Id. at 285, 98 S.Ct. at 1064-65, 55 L.Ed.2d at 282-83 (Burger, C. X, concurring in the judgment).
. Id. at 285, 98 S.Ct. at 1065, 55 L.Ed.2d at 283. The Chief Justice suggested that the per se rule might admit of an exception where police officers were shown to have searched for the specific purpose of discovering witnesses. See id. at 284, 98 S.Ct. at 1064 & n. 4, 55 L.Ed.2d at 292 & n. 4; cf. p. - of 191 U.S.App.D.C., p. 991 of 590 F.2d & note 75 supra.
. 435 U.S. at 275, 98 S.Ct. at 1059, 55 L.Ed.2d at 276, quoting 371 U.S. at 486, 83 S.Ct. 407.
. 435 U.S. at 275, 276, 98 S.Ct. at 1060-61, 55 L.Ed.2d at 277-78.
. Id. at 279, 98 S.Ct. at 1061, 55 L.Ed.2d at 279.
. Id., at 278, 98 S.Ct. at 1061, 55 L.Ed.2d at 278.
. Id., at 278, 98 S.Ct. at 1061, 55 L.Ed.2d at 278.
. Id., at 276, 98 S.Ct. at 1060, 55 L.Ed.2d at 277, citing 422 U.S. at 603, 95 S.Ct. 2254.
. 435 U.S. at 280, 98 S.Ct. at 1062, 55 L.Ed.2d at 279.
. Some of the evidence improperly seized from the file folder apparently was used in questioning Massa, whereas the illegally seized evidence was not used in questioning the witness in Ceccolini. See, 435 U.S. at 279, 98 S.Ct. at 1062, 55 L.Ed.2d at 279. Neither Massa’s identity nor his relationship with Scios was known to the FBI before the search, whereas “both the identity of [the witness] and her relationship with the respondent [were] well known to” the investigators in Ceccolini. See id., at 279, 98 S.Ct. at 1062, 55 L.Ed.2d at 279. It is unclear how much weight the Court meant to accord this latter factor, since it accepted the findings of both lower courts that “the ongoing investigation would not have inevitably led” to discovery of the witness in question. See id., at 273, 98 S.Ct. at 1058, 55 L.Ed.2d at 275.
. 422 U.S. at 603, 95 S.Ct. at 2261.
. 435 U.S. at 279, 98 S.Ct. at 1062, 55 L.Ed.2d at 279.
. Id., at 275, 98 S.Ct. at 1059, 55 L.Ed.2d at 276 (emphasis original).
. 406 U.S. 356, 92 S.Ct. 1620, 32 L.Ed.2d 152 (1972).
. Id. at 365, 92 S.Ct. at 1626, quoting Wong Sun v. United States, 371 U.S. 471, 488, 83 S.Ct. 407, 9 L.Ed.2d 441 (1963).
. 422 U.S. at 603-04, 95 S.Ct. 2254, citing 406 U.S. at 365, 92 S.Ct. 1620.
. 422 U.S. at 604, 95 S.Ct. at 2262 (footnote omitted).
. 435 U.S. at 280, 98 S.Ct. at 1062, 55 L.Ed.2d at 279.
. 417 U.S. at 447, 94 S.Ct. at 2365.
. 422 U.S. at 612, 95 S.Ct. at 2266 (Powell, J., concurring in part).
. 395 U.S. 752, 89 S.Ct. 2034, 23 L.Ed.2d 685 (1969) (valid search incident to arrest limited to area “within the immediate control” of arrestee).
. Tr. II 30-31.
. See Brown v. Illinois, 422 U.S. at 610-11, 95 S.Ct. 2254 (Powell, J., concurring in part).
. 435 U.S. at 276, 98 S.Ct. at 1060, 55 L.Ed.2d at 277.
. Id. at 279, 98 S.Ct. 1062, 55 L.Ed.2d at 279.
. See p. - of 191 U.S.App.D.C., p. 983 of 590 F.2d & note 26 supra.
. See Parker v. Estelle, 498 F.2d 625, 630 (5th Cir. 1974), cert. denied, 421 U.S. 963, 95 S.Ct. 1951, 44 L.Ed.2d 450 (1975). Cf. United States v. Paepke, 550 F.2d 385, 390 (7th Cir. 1977) (defendant’s consultation of lawyer regarding tax returns purges taint of illegal search, allowing illegally seized evidence to be used in criminal prosecution for tax fraud committed after search) (citing Scios panel opinion).
. Maj. op. at - of 191 U.S.App.D.C., at 961 of 590 F.2d (emphasis added).
. United States v. Houltin, 566 F.2d 1027, 1031-32 (5th Cir. 1978) (alternate holding).
. See Brown v. United States, 126 U.S.App.D.C. 134, 139, 375 F.2d 310, 315, cert. denied, 388 U.S. 915, 87 S.Ct. 2133, 18 L.Ed.2d 1359 (1967) (strong evidence that witness agreed to testify after promise of non-prosecution); United States v. Beasley, 485 F.2d 60, 64 (10th Cir. 1973), cert. denied, 416 U.S. 941, 94 S.Ct. 1946, 40 L.Ed.2d 292 (1974) (“[W]hen the testimony of an accessory- is used there would often exist grounds for ruling that the giving of the testimony results from the accessory’s desire to help himself or herself. Thus, the exercise of human volition intervenes and it is not the product of the unlawful arrest.”).
. See United States v. Marder, 474 F.2d 1192, 1197 n. 6 (5th Cir. 1973); United States v. Evans, 454 F.2d 813, 819 (8th Cir.), cert. denied, 406 U.S. 969, 92 S.Ct. 2423, 32 L.Ed.2d 668 (1972); United States v. Hoffman, 385 F.2d 501, 504 (7th Cir. 1967), cert. denied, 390 U.S. 1031, 88 S.Ct. 1424, 20 L.Ed.2d 288 (1968); Edwards v. United States, 117 U.S.App.D.C. 383, 384, 330 F.2d 849, 850 (1964); Smith and Bowden v. United States, 117 U.S.App.D.C. 1, 2, 3, 324 F.2d 879, 880, 881 (1963), cert. denied, 377 U.S. 954, 84 S.Ct. 1632, 12 L.Ed.2d 498 (1964).
. 435 U.S. at 277, 98 S.Ct. at 1060, 55 L.Ed.2d at 277 (emphasis added).