Reed Hamilton was convicted in Iowa state court of first degree murder and voluntary manslaughter for the deaths of Cathy Larson and Nick Pappas, Jr. The Iowa Supreme Court affirmed both convictions on direct appeal. State v. Hamilton, 335 N.W.2d 154 (Iowa 1983). Hamilton then petitioned under 28 U.S.C. § 2254 for a writ of habeas corpus. He alleged that (1) key prosecution witnesses and certain evidence admitted at trial were discovered only because of earlier police violations of his Fifth and Sixth Amendment rights, and, thus, being “fruit of the poisonous tree,” were improperly admitted at trial; (2) improper statements made by the prosecution during its opening statement and its closing argument deprived him of a fair trial; and (3) there was insufficient evidence to convict him of first degree murder on a felony murder theory. The District Court1 rejected each of those contentions and denied the petition. Hamilton v. Nix, Civil No. 83-454-B (S.D.Iowa June 27, 1984) (unpublished memorandum opinion and order). Hamilton appealed, and a panel of this Court, with one judge dissenting, reversed, holding that the state trial court committed constitutional error in admitting certain witness testimony and physical evidence as part of the prosecution’s case. The panel reasoned that the challenged testimony and evidence were “fruit of the poisonous tree” because their discovery and procurement were “inextricably linked” with the prior police misconduct, and concluded that the evidence was not admissible under the “attenuation,” “independent source,” or “inevitable discovery” exceptions to the exclusionary rule. Hamilton v. Nix, 781 F.2d 619 (8th Cir.1985) (panel opinion). In so holding, the panel applied the analysis set forth in United States v. Ceccolini, 435 U.S. 268, 98 S.Ct. 1054, 55 L.Ed.2d 268 (1978). This Court granted the State’s petition for rehearing en banc. For the reasons discussed below, we affirm the District Court’s denial of Hamilton’s petition for a writ of habeas corpus.2
*465I.
Hamilton’s first contention is that key prosecution witnesses and evidence admitted at trial were discovered by the police as a result of their prior misconduct; thus, such evidence was “fruit of the poisonous tree” and was improperly admitted at trial. Specifically, Hamilton challenges the admission of (1) Maxine Hamilton’s testimony regarding a telephone conversation during which Reed Hamilton confessed to the killings; (2) the trial testimony of Maxine Hamilton and Paul Lincoln regarding a suitcase containing ten pounds of marijuana; and (3) the marijuana itself.
On this appeal the State does not deny that police misconduct occurred.3 The State’s argument is that all the challenged testimony of Maxine Hamilton and Paul Lincoln was nonetheless admissible under the “independent source” exception to the exclusionary rule. We agree that the identity and testimony of Hamilton and Lincoln derived from lawful sources independent of the police misconduct, and, therefore, that the trial court did not err in admitting their testimony.
The trial below was the second in this case. Both Maxine Hamilton and Paul Lincoln refused to testify at the first trial, and, consequently, both were held in contempt of court and sentenced to short jail terms. Both were subpoenaed again to testify at the second trial, and this time both testified on behalf of the prosecution. Maxine Hamilton testified that Reed Hamilton had borrowed a handgun from her about one month before the killings. She testified that on the day of the killings Reed Hamilton carried a blue suitcase into her house and took it downstairs to leave in her basement, but that she never looked into the suitcase. She also testified about her telephone conversation with Reed Hamilton during which he admitted killing Pap-pas and Larson and asked her to remove the suitcase of marijuana from her house. Paul Lincoln testified that on the day of the killings Reed Hamilton carried a suitcase containing two large green bags into the basement of Maxine Hamilton’s house. Lincoln later went to the basement, opened the suitcase, and saw “some kind of tobacco” with a “strange smell.”
Under the “fruit of the poisonous tree” doctrine, the exclusionary rule bars the admission of physical evidence and live witness testimony obtained directly or indirectly through the exploitation of police illegality. See Wong Sun v. United States, 371 U.S. 471, 484-88, 83 S.Ct. 407, 415-18, 9 L.Ed.2d 441 (1963). The Supreme Court, however, has recognized three analytically distinct exceptions to this doctrine. The Court has suggested that the underlying focus of analysis is “ ‘whether, granting establishment of the primary illegality, the evidence to which instant objection is made has been come at by exploitation of that illegality or instead by means sufficiently distinguishable to be purged of the primary taint.’ ” Id. at 488, 83 S.Ct. at 417 (citation omitted). Thus, under the “independent source” doctrine, the challenged evidence will be admissible if the prosecution can show that it derived from a lawful source independent of the illegal conduct. Silverthorne Lumber Co. v. United States, 251 U.S. 385, 392, 40 S.Ct. 182, 183, 64 L.Ed. 319 (1920). In such a case, there is no reason to exclude the challenged evidence since the police misconduct is not even a “but for” cause of its discovery. Second, challenged evidence will be admissible under the “attenuation” doctrine, even though it did not have an independent source, if the causal connection between the constitutional violation and the dis*466covery of the evidence has become so attenuated as to dissipate the taint. United States v. Ceccolini, 435 U.S. at 273-80, 98 S.Ct. at 1058-62. Third, challenged evidence will be admissible under the “inevitable (or ultimate) discovery” doctrine if the prosecution can establish that it inevitably would have been discovered by lawful means without reference to the police misconduct. Nix v. Williams, 467 U.S. 431, 444, 104 S.Ct. 2501, 2509, 81 L.Ed.2d 377 (1984).
Hamilton argues that Maxine Hamilton’s and Paul Lincoln’s testimony was not admissible under any of these three exceptions, and urges us to adopt the same reasoning used by the panel majority, which focused primarily on the “attenuation” analysis set forth in Ceccolini. We believe, however, that the panel majority read Ceccolini too broadly, and, consequently, that it erred in applying attenuation analysis in this case to exclude Maxine Hamilton’s and Paul Lincoln’s testimony.
In Ceccolini, a police officer, while taking a break in the defendant’s business shop, noticed an envelope containing money lying on the cash register. Upon closer examination, he found that it also contained slips of paper indicating unlawful gambling activity. He then questioned one of the defendant’s employees, who told him that the envelope belonged to the defendant. The officer forwarded this information to an FBI agent, who later interviewed the employee without referring to the incident involving the police officer. The defendant later testified falsely before a federal grand jury that he had never been involved in any way with gambling operations. His employee testified for the prosecution at his subsequent trial for perjury. The defendant sought to suppress his employee’s testimony as “fruit of the poisonous tree.” The trial court granted the motion, reasoning that the employee-witness “first came directly to the attention of the government as a result of an illegal search.” 435 U.S. at 273, 98 S.Ct. at 1058. The court of appeals affirmed, but the Supreme Court reversed. In reversing, the Supreme Court set forth an analytical framework to evaluate the admissibility of live witness testimony under the attenuation doctrine. Id. at 274-79, 98 S.Ct. at 1059-61.
The Ceccolini attenuation analysis does not apply, however, absent an initial factual determination that the identity of the witness whose testimony is challenged was discovered as a result of the constitutional violation. See id. at 276 & n. 4, 277, 98 S.Ct. at 1060, & n. 4, 1060. Indeed, the identity of the witness in Ceccolini was discovered only because of the unlawful search by the police officer. Attenuation analysis is inappropriate, however, in a case, such as here, in which the police already are aware of the witness’s identity and involvement. See United States v. Crews, 445 U.S. 463, 471-72, 100 S.Ct. 1244, 1249-50, 63 L.Ed.2d 537 (1980). Moreover, application of the Ceccolini analysis beyond its factual context, as was done by the panel majority, would eviscerate the independent source exception to the exclusionary rule.
The independent source doctrine was first recognized by the Supreme Court in Silverthome Lumber. The Court there stated:
The essence of a provision forbidding the acquisition of evidence in a certain way is that not merely evidence so acquired shall not be used ... but that it shall not be used at all. Of course this does not mean that the facts thus obtained become sacred and inaccessible. If knowledge of them is gained from an independent source they may be proved like any others____
251 U.S. at 392, 40 S.Ct. at 183. The rationale for the independent source doctrine was explained by the Court in Nix v. Williams:
[T]he derivative evidence analysis ensures that the prosecution is not put in a worse position simply because of some earlier police error or misconduct. The independent source doctrine allows admission of evidence that has been discovered by means wholly independent of any *467constitutional violation____ The independent source doctrine teaches us that the interest of society in deterring unlawful police conduct and the public interest in having juries receive all probative evidence of a crime are properly balanced by putting the police in the same, not a worse, position that they would have been in if no police error or misconduct had occurred. When the challenged evidence has an independent source, exclusion of such evidence would put the police in a worse position than they would have been in absent any error or violation.
467 U.S. at 443, 104 S.Ct. at 2509 (footnote and citations omitted). The critical inquiry under the independent source doctrine is whether the challenged evidence was obtained from lawful sources and by lawful means independent of the police misconduct. Segura v. United States, 468 U.S. 796, 805, 814, 104 S.Ct. 3380, 3386, 82 L.Ed.2d 599 (1984); Nix v. Williams, 467 U.S. at 459, 104 S.Ct. at 2517 (Brennan, J., dissenting); see Crews, 445 U.S. at 471-72, 475, 100 S.Ct. at 1249-50, 1252.
In this case that inquiry clearly must be resolved in favor of the State. Before any police misconduct occurred, the police were well aware of Maxine Hamilton’s identity and involvement in the case. The Iowa Supreme Court found as follows:
The police interrogation of Hamilton must be divided into two distinct segments, that preceding the suggestion of help and that following it. The interrogation began at police headquarters at approximately 9:20 p.m. on the day following the shooting. Hamilton was properly advised of his Miranda rights, and no issue is raised in that regard. The interrogation continued without a problem until approximately 11:00 p.m., when the suggestion of help was made, and the tainting of the confession allegedly occurred. During this pre-tainting segment of the interrogation, Hamilton furnished considerable information. He said he had gone to the victims’ house between 3:00 and 3:30 p.m. on the day of the shooting and that Nick Pappas and Cathy Larson were there at that time. He said he purchased some marijuana from Pappas and left for home, where he and his fiancee, Diane Nystrum, stayed until about 8:00 p.m. when they went shopping and to his mother’s house before returning home. He stated that just prior to going to bed, Diane had seen a shadow outside the house and that he had gone upstairs to get his shotgun. He said he had sat up all night to protect the home with his shotgun. The officers then asked him if he had any guns besides the shotgun. Hamilton replied that he had a .38 caliber revolver and, when asked where it was, responded that it was “over to his mother’s house.” (Investigation of the killing had established that a .38 caliber weapon had been used.) Immediately following the defendant’s statement about his revolver being at his mother’s house, several of the officers left the interrogation room to type up a search warrant application for the mother’s house, apparently for the gun and marijuana. It was at this point, when the other officers had left, that Hamilton asked the remaining officer to lock the door and confided to the officer that he “needed help.” The officer’s response that he would try to help, according to the trial court’s suppression order, then tainted the remainder of the statement.
Before the tainting occurred, the identity and possible involvement of Hamilton’s mother were known to the officers. The later, tainted, portion of the statement, more clearly focused on the extent of her involvement and contradicted portions of his earlier statement as it pertained to her. For example, in the second half of his statement, he said the gun was not at his mother’s house as he originally said but was, in fact, on the bottom of a river. Nevertheless, at the point at which the tainting occurred, the police had already learned about the mother’s involvement; their investigation was far from an aimless search for evidence which was dependent for direction upon anything Hamilton said later. The *468police knew at that point the mother’s house had figured prominently in Hamilton’s activities the previous day and had good reason to believe both the marijuana and murder weapon could be found there.
335 N.W.2d at 159. None of these facts is in dispute. In any event, the state court’s determinations of factual issues are entitled to the statutory presumption of correctness under 28 U.S.C. § 2254(d).
Though conceding that the police were aware of Maxine Hamilton’s identity and potential as a witness before any police misconduct occurred, the panel majority did not accord that fact much weight “given the strength of the evidence of the involuntariness of Maxine Hamilton’s testimony.” 781 F.2d at 627. The panel majority placed great emphasis on the fact that the State had to subpoena Maxine Hamilton to testify. In the panel’s opinion, because her testimony was “coerced” (in the sense that she testified only under subpoena), it was not admissible under the independent source exception. Id. at 628 n. 11.
The fact that a witness testified only under subpoena does not render the source of that witness’s identity or the means by which the witness’s testimony was obtained any less lawful. See Crews, 445 U.S. at 472, 100 S.Ct. at 1250 (“Here the victim’s identity was known long before there was any official misconduct, and her presence in court is thus not traceable to any Fourth Amendment violation.”). Though that may be a relevant factor under the Ceccolini attenuation analysis, it is not a relevant factor under an independent source analysis. It is one thing to exclude evidence obtained in an unlawful manner; it is quite another to exclude the testimony of a witness whose identity was lawfully discovered. See Segura, 468 U.S. at 814, 104 S.Ct. at 3391; Crews, 445 U.S. at 471-72, 475, 100 S.Ct. at 1249-50, 1252 (“The exclusionary rule enjoins the Government from benefitting from evidence it has unlawfully obtained; it does not reach backward to taint information that was in official hands prior to any illegality.”); cf. United States v. Leonardi, 623 F.2d 746, 752 (2d Cir.), cert. denied, 447 U.S. 928, 100 S.Ct. 3027, 65 L.Ed.2d 1123 (1980). The State has a right to every witness’s testimony except in those narrow circumstances where the law recognizes a privilege on grounds of public policy. Cf Branzburg v. Hayes, 408 U.S. 665, 688, 92 S.Ct. 2646, 2660, 33 L.Ed.2d 626 (1972) (noting the “longstanding principle that ‘the public ... has a right to every man’s evidence’ ”); Segura, 468 U.S. at 816, 104 S.Ct. at 3392 (rejecting the suggestion that there is a “constitutional right” to destroy evidence). Acceptance of the panel’s reasoning, however, would create an additional privilege for any witness who, though lawfully discovered and subpoenaed, refuses to cooperate with the police or prosecution, and would superimpose attenuation analysis upon the independent source doctrine.
As the Iowa Supreme Court found, the police were aware of Maxine Hamilton’s involvement and her importance as a witness from voluntary statements made by Reed Hamilton during his interrogation on the evening of January 26, 1978. The telephone conversation about which Maxine Hamilton testified occurred the following morning (several hours after interrogation had ceased) when Reed Hamilton was permitted to make a telephone call. The telephone conversation was in no sense part of or tainted by the earlier unlawful police conduct that rendered some of his confession involuntary. The State lawfully had learned of Maxine Hamilton’s involvement in the case and it lawfully procured her attendance and testimony at trial with a subpoena. It would be an ironic rule of law to exclude a critical witness’s testimony in these circumstances simply because the police had unlawfully obtained some of the same information during the course of their investigation. That would place the State not in the same position it would have been in had no police misconduct occurred, but in a worse position, contrary to the Supreme Court’s admonition in Nix v. Williams. 467 U.S. at 443, 104 S.Ct. at 2509. Reed Hamilton voluntarily provided *469the police with information identifying his mother as a witness with valuable knowledge. He cannot now complain that the State took advantage of that information by lawfully subpoenaing his mother to testify at his trial. We hold that Maxine Hamilton’s testimony was admissible under the “independent source” exception, and that the state trial court did not err in admitting it.
For the same reasons, we hold that Paul Lincoln’s testimony was admissible under the independent source exception. At no time during his interrogation did Reed Hamilton mention Lincoln’s name. The police lawfully discovered Lincoln (who was living with Maxine Hamilton at the time of the events involved in this case) during the course of their investigation, and they lawfully procured his attendance and testimony at trial with a subpoena. Thus, Lincoln’s testimony was admissible under the independent source exception, and the trial court committed no error in admitting it.
The admission of the marijuana itself, however, presents a different situation. It is not seriously disputed that the marijuana was a fruit of unlawful police conduct. The police took Hamilton to his mother’s house, after he had been promised leniency, to seek her cooperation in recovering the marijuana. Only then did Maxine Hamilton retrieve the suitcase and give it to the police. The State concedes that the marijuana was not admissible under either the independent source, attenuation, or inevitable discovery exception.
At trial the State sought to justify the admission of the marijuana on the ground that the defense had “opened the door” to its admission by cross-examining Maxine Hamilton about her activities in regard to the suitcase of marijuana. The trial judge admitted the marijuana as “rebuttal testimony.” The State does not explain in its brief exactly what evidence or testimony it sought to rebut by introducing the marijuana. Nor are we able to discern from the trial transcript a proper reason for its admission as rebuttal evidence. Therefore, we hold that its admission into evidence was error. Compare Agnello v. United States, 269 U.S. 20, 46 S.Ct. 4, 70 L.Ed. 145 (1925) and United States v. James, 555 F.2d 992 (D.C.Cir.1977) with Walder v. United States, 347 U.S. 62, 74 S.Ct. 354, 98 L.Ed. 503 (1954). Our review of the entire trial transcript convinces us, however, that the error was harmless. There was strong circumstantial evidence to permit the jury to conclude beyond a reasonable doubt that Hamilton had robbed Pappas of marijuana. See Part III, infra. The marijuana itself added little if anything to the State’s case. Thus, it was harmless error to admit it into evidence. See Milton v. Wainwright, 407 U.S. 371, 92 S.Ct. 2174, 33 L.Ed.2d 1 (1972).
II.
Hamilton next contends that improper remarks by the prosecutor in the opening statement and in the closing argument were prejudicial and deprived him of a fair trial.
During closing argument, the prosecutor suggested that there was sufficient circumstantial evidence to convict Hamilton of first degree murder under either a premeditation theory or a felony murder theory. The prosecutor stated, “So on both theories there’s ample evidence clearly in this case, evidence of a first degree murder as to both Nick Pappas and Kathy Larson____” Trial Transcript at 547. The defense objected and moved for a mistrial on the ground that it was improper to argue first degree murder as to Pappas since the State had charged Hamilton with only voluntary manslaughter for Pappas’s death. For reasons not apparent in the record, Hamilton had been charged with first degree murder only for Larson’s death. The trial judge sustained the objection, admonished the prosecutor, and immediately instructed the jury to disregard the prosecutor’s remark. The trial judge denied the motion for mistrial. The prosecutor then concluded his closing argument without further incident. Hamilton argues on appeal that the prose*470cutor’s improper remark “so infected the trial with unfairness as to make the resulting conviction a denial of due process.” Donnelly v. DeChristoforo, 416 U.S. 637, 643, 94 S.Ct. 1868, 1871, 40 L.Ed.2d 431 (1974).
In a § 2254 habeas corpus proceeding, a federal court’s review of alleged due process violations stemming from a state court conviction is narrow.4 The petitioner must show that the alleged improprieties were “so egregious that they fatally infected the proceedings and rendered his entire trial fundamentally unfair.” Moore v. Wyrick, 760 F.2d 884, 886 (8th Cir.1985); see Darden v. Wainwright, — U.S. -, 106 S.Ct. 2464, 2472, 91 L.Ed.2d 144 (1986); Donnelly v. DeChristoforo, 416 U.S. at 642-43, 94 S.Ct. at 1871; Smith v. Phillips, 455 U.S. 209, 219, 102 S.Ct. 940, 947, 71 L.Ed.2d 78 (1982). To carry that burden, the petitioner must show that there is a reasonable probability that the error complained of affected the outcome of the trial —i.e., that absent the alleged impropriety the verdict probably would have been different. See Kirkpatrick v. Blackburn, 777 F.2d 272, 278-79 (5th Cir.1985); United States ex rel. Shaw v. De Robertis, 755 F.2d 1279, 1281 n. 1 (7th Cir.1985).
Applying that narrow standard of review to the present case, we cannot say that the prosecutor’s lone remark, when viewed in the context of the entire trial and not in isolation, see Donnelly v. DeChristoforo, 416 U.S. at 643, 94 S.Ct. at 1871, deprived Hamilton of a fair trial. The improper conduct challenged here consisted of a single remark during closing argument. After being admonished by the trial judge, the prosecutor made no other improper remarks. The trial judge gave a cautionary instruction to the jury immediately after the improper remark. Moreover, the evidence of Hamilton’s guilt was overwhelming. We hold that Hamilton has not met his burden of showing a reasonable probability that absent the improper remark the jury’s verdict would have been different.
Hamilton’s objections to the opening statement concern the prosecutor’s references to items of evidence and to testimony of witnesses he believed would be introduced during the prosecution’s case-in-chief. Our holding in Part I, supra, regarding the admissibility of Maxine Hamilton’s and Paul Lincoln’s testimony disposes in part of Hamilton’s contention here. Hamilton also objects to the prosecutor’s references to the testimony of Edwin Kracht, a police investigator. Kracht testified to the State’s theory of Hamilton’s route following the killings and the approximate time and distance between various points along that route. Hamilton contends that Kracht’s testimony was based solely on information provided by Hamilton when he retraced his route with the police. The state trial judge previously had excluded any reference to information derived solely from that excursion because it was tainted by police misconduct.
A review of the trial transcript convinces us that all the information on which Kracht relied was lawfully obtained from sources independent of the information provided by Hamilton. Evidence from various witnesses (whose identity and testimony were lawfully obtained) provided a reasonably accurate account of Hamilton’s actions following the killings. For example, Doug*471las Millin testified that he saw Hamilton at the Pappas residence at approximately 5:30 p.m. on the day of the killings. Martin Grund, a childhood acquaintance of Hamilton’s, testified that Hamilton arrived at his house wearing wet clothing at 6:00 p.m. Hamilton told Grund that he accidentally had fallen in the river. Paul Lincoln testified that Hamilton returned to his mother’s house at 6:30 p.m. Since Kracht’s testimony was based on information lawfully obtained from sources independent of the police misconduct, the prosecutor committed no impropriety in referring to this testimony in his opening statement.
III.
Hamilton’s final contention is that there was insufficient evidence from which a jury reasonably could conclude that he was guilty of first degree murder on a felony murder theory, the predicate felony being a robbery. Hamilton argues that there was no evidence to connect the marijuana he carried into his mother’s house with the Pappas residence, and, thus, no evidence that a robbery had occurred.
All three reviewing courts that previously have addressed this issue have held that there was sufficient circumstantial evidence to permit the jury reasonably to infer that Hamilton had robbed Pappas of a large quantity of marijuana. See Hamilton v. Nix, 781 F.2d at 629 n. 13 (panel opinion); Hamilton v. Nix, No. 83-454-B, slip op. at 9-10 (District Court opinion); State v. Hamilton, 335 N.W.2d at 161 (Iowa Supreme Court opinion). Our independent review of the entire trial transcript leads us to the same conclusion. There was evidence that both Hamilton and Pap-pas were drug dealers, and that Hamilton had made an appointment with Pappas to transact a drug deal on the day of the killings. There was evidence that on the day before the killings Pappas had $4600 (an amount sufficient to buy ten pounds of marijuana) and that he usually purchased large quantities of drugs (intended for resale to his customers or to other drug dealers) shortly before the scheduled transaction. There was evidence that Hamilton had a .38 caliber gun, that he was at the Pappas residence at the approximate time of the killings, and that Pappas and Larson were shot with a .38 caliber weapon. There was evidence that shortly after the time of the killings Hamilton carried a suitcase containing, according to Paul Lincoln, two bags full of “some kind of tobacco” with a “strange smell” into the house Lincoln shared with Maxine Hamilton, secretly hid it in the basement, and later asked his mother to remove it from the house to conceal it from the police. We are satisfied there was sufficient circumstantial evidence from which the jury could find beyond a reasonable doubt that Hamilton robbed Pappas of marijuana and killed Larson during the course of that robbery. See Jackson v. Virginia, 443 U.S. 307, 318-19, 99 S.Ct. 2781, 2788-89, 61 L.Ed.2d 560 (1979).
The District Court’s denial of Hamilton’s petition for a writ of habeas corpus is affirmed.
. The Honorable Harold D. Vietor, United States District Judge for the Southern District of Iowa.
. Because the facts of this case have been thoroughly discussed in the two prior published opinions, see Hamilton v. Nix, 781 F.2d 619 (8th Cir.1985); State v. Hamilton, 335 N.W.2d 154 (Iowa 1983), we will not restate them here. Instead, we will refer to particular facts as necessary in the course of our analysis.
. The State concedes that Detective Haviland’s promises of leniency to Hamilton during interrogation rendered Hamilton’s subsequent incriminating statements involuntary. Those statements were excluded from evidence by the trial court at both trials in this case. The State likewise concedes that the police violated Hamilton’s Sixth Amendment right to counsel when they elicited incriminating information from Hamilton regarding his actions after the killings. It was at this time that Hamilton accompanied the police and retraced his route from the Pappas residence after the killings and requested his mother to cooperate with the police. See Part II, infra, at 469-71.
. The standard and burden of proof are different, of course, when we are considering on direct appeal claims of error in a federal criminal trial. On direct appeal, however, we are exercising our supervisory power over matters of judicial administration in the federal district courts. See, e.g., United States v. Hernandez, 779 F.2d 456 (8th Cir.1985) (abuse of discretion standard applied to claim of prosecutorial misconduct). Thus, not every trial error that might result in reversal of a federal conviction on direct appeal would mandate the same result in a § 2254 review of a state court conviction, where we may consider only errors of constitutional magnitude. See Darden v. Wainwright, — U.S.-, 106 S.Ct. 2464, 2472, 91 L.Ed.2d 144 (1986) (“[T]he appropriate standard of review for such a claim on writ of habeas corpus is ‘the narrow one of due process, and not the broad exercise of supervisory power.’”) (quoting Donnelly v. DeChristoforo, 416 U.S. at 642, 94 S.Ct. at 1871); Smith v. Phillips, 455 U.S. 209, 221, 102 S.Ct. 940, 71 L.Ed.2d 78 (1982).