The only issue warranting discussion in this case concerns the trial judge’s refusal to permit defense counsel to cross-examine a government witness on the daily dosage of a heroin addict.1
Appellant was convicted of two counts of federal narcotic violations based on his possession of 36 capsules of heroin. Count one was based on 26 U.S.C. § 4704 (a), which requires the government to prove that appellant knowingly purchased, dispensed or distributed heroin not in or from the original tax-stamped package. This statute permits, but does not require, the jury to infer guilt from *1173evidence of possession.2 Count two was based on 21 U.S.C. § 174, which requires the government to prove that appellant received or concealed illegally imported heroin which he knew had been brought into this country contrary to law.3 This statute permits, but does not require, the jury to infer knowledge of illegal importation from evidence of possession.
The government’s case depended upon these statutory inferences.4 Appellant says he might have persuaded the jury not to draw the inferences if he had been permitted to show that the 36 capsules of heroin with which he was found would be little more than a one day supply for an addict.5 He never did get to bring this fact to the jury’s attention, however, for his cross-examination of a government witness was cut short:
Defense Counsel: Officer Johnson,
how long have you been in the Narcotics Squad?
Witness: I was in the Narcotics Squad for two and a half years.
Defense Counsel: And you have become fairly familiar with the habits of narcotics addicts?
Witness: Yes, sir. Defense Counsel: Based on your own experience, how long do you think it would take an addict to use the 36 capsules of heroin?
Prosecutor: I would object.
Court: The objection is sustained.
The prosecutor did not state the grounds of his objection; 6 the judge did not ask defense counsel to respond to the objection, nor did he give his reason for sustaining the objection; and defense counsel did not make a proffer of the information he expected to elicit, nor did he explain why the testimony was needed.
The government’s only argument in this court is that its objection was properly sustained because the testimony sought was irrelevant. It relies wholly on the Supreme Court’s approval of the statutory inferences in Turner v. United States.7 That case, however, simply upheld the statutory inferences against due process attack. Under Turner the jury is permitted, but is by no means required, to draw an inference of guilt from evidence of possession. It is still the rule that “[t]he jury must be left free to believe * * * any evidence” which tends to show that the defendant is not guilty of the crime charged despite his possession of narcotics.8
*1174The excluded testimony was plainly relevant here, for the fact that 36 capsules of heroin may be only a personal supply tends to cast doubt on appellant’s guilt. With respect to the first count (26 U.S.C. § 4704(a)) the evidence might have raised a reasonable doubt whether appellant had purchased the drug, rather than having found, stolen or been given so small an amount. But even more important, the excluded testimony clearly raises the question whether appellant would be likely to dispense or distribute his limited supply of heroin.9 And since we do not know whether the jury found that appellant purchased, or that he dispensed, or that he distributed the narcotic, we cannot say that the exclusion had no impact.10 With respect to the second count (21 U.S.C. § 174) the fact that appellant possessed an amount of heroin likely to be intended only for his own use casts doubt upon the inference that he was sufficiently involved in the heroin trade to know whether the drugs had been illegally imported.11
The dissent suggests that the trial judge might have sustained the prosecutor’s general objection because the question touched on matters beyond the limits of the direct examination. We reject this sort of speculation. To be sure, when an objection is sustained for the wrong reason, or for no discernible reason, an appellate court may affirm if it clearly appears that the evidence is inadmissible under any circumstances.12 In such event the ruling below is harmless error. But it is not harmless where, as here, the party offering the evidence could have taken corrective action (e. g„ calling the witness as his own) if he had known the ground which the dissent now imputes to the objection.13 Moreover, there is no basis in this record for determining how the trial judge would have exercised his broad discretion to decide whether the cross-examination exceeded the scope of the direct if he had been called upon to do so.14
*1175The search for truth in this trial might not have aborted if the participants had known what was on each others’ minds. The prosecutor should have stated the basis of his objection. And, although confronting a judge after he has ruled may be risky business, defense counsel should have proffered the testimony he expected to elicit. But the basic responsibility for making a proper evidentiary ruling must lie with the trial judge. Therefore — except where the reason for the objection is obvious to all15 — the judge should refrain from an immediate ruling, and should inquire into the ground of the objection and the basis of the question asked. The judge should then state the reason for his ruling.16 Aside from facilitating appellate review, this procedure ensures both that the judge makes an informed decision and that the party opposing the objection has an opportunity to take appropriate corrective action.
For the reasons stated,17 we reverse the convictions on counts one and two so that a new trial can be held.18
It is so ordered.
. Appellant also claims that there was no probable cause for his arrest. He argues, essentially, that the trial judge erred in crediting the arresting officer’s testimony because of certain inconsistencies therein. Our review of the transcripts, however, convinces us that the judge’s findings of fact were not clearly erroneous.
. Turner v. United States, 396 U.S. 398, 419-422, 90 S.Ct. 642, 655, 24 L.Ed.2d 610 (1970) upheld the inference of purchase from evidence of possession, but struck down the inference of dispensing or distributing, “for the bare fact of possessing heroin is far short of sufficient evidence from which to infer * * * these acts.”
. See id. at 405-407, 90 S.Ct. 642; Harris v. United States, 359 U.S. 19, 23, 79 S.Ct. 560, 3 L.Ed.2d 843 (1959).
. The evidence introduced by the government showed only that a police officer saw appellant shake some capsules out of a small manilla envelope and display them to a companion. At that moment the companion spotted the officer and fled. Appellant was then arrested and searched, and the contraband uncovered.
. Compare Watson v. United States, 141 U.S.App.D.C. -, 439 F.2d 442 (1970) (en banc) (13 capsules of heroin was one-half Watson’s daily habit).
. Cf. F.R.Cr.P. 51, which abolishes formal exceptions and states that in place of an exception “it is sufficient that” the objecting party “makes known to the court the action which he desires the court to take or his objection to the action of the court and the grounds therefor * * (Emphasis added.) This rule assures that the trial judge makes an informed decision, and allows the judge and opposing counsel to take whatever corrective action is needed. See 8A Moore, Federal Practice f 51.02 (1970). Both of these purposes would have been well served here had the prosecutor stated the grounds of his objection.
. Supra note 2.
. United States v. Peeples, 377 F.2d 205, 210 (2d Cir. 1967) (dealing with the inference of knowledge of illegal importa*1174tion from evidence of possession in 21 U.S.C. § 174) ; cf. United States v. Glaziou, 402 F.2d 8, 16 (2d Cir. 1968), cert. denied, 393 U.S. 1121, 89 S.Ct. 999, 22 L.Ed.2d 126 (1969).
The admission of such evidence is particularly important where, as here, the defendant exercises his privilege not to testify, for he otherwise cannot rebut the inferences which flow from evidence of possession of narcotics.
. This is so whether the jury found that appellant dispensed or distributed heroin by relying on the statutory inference (since declared invalid in Turner v. United States, supra note 2 at 421, 90 S.Ct. 642) or by believing that appellant “was in the process of” dispensing or distributing (see id. at 420, 90 S.Ct. 642) when arrested, see note 4, supra. Speaking of cocaine in Turner, the Supreme Court noted that “having a small quantity * * * is itself consistent with [appellant’s] possessing the [drug] not for sale but exclusively for his personal use.” Id. at 423, 90 S.Ct. at 656.
. See, e. g., Street v. New York, 394 U.S. 576, 585-588, 89 S.Ct. 1354, 22 L.Ed.2d 572 (1969) and cases cited; United States v. Romano, 382 U.S. 136, 138, 86 S.Ct. 279, 15 L.Ed.2d 210 (1965).
. Compare Turner v. United States, supra note 2 at 406 & n. 6, 416-417, 90 S.Ct. 642.
The jury obviously had some difficulty with the question of appellant’s knowledge of illegal importation, for after perhaps an hour of deliberation it sent the following note to the judge (emphasis in the original) :
In regard to the “Second Count” on the indictment, idease clarify the following terms for our clear understanding:
1) concealment
2) imported into the United States contrary to law, WITH THE KNOWLEDGE
. See, e. g., McMahon v. Matthews, 48 App.D.C. 303 (1919) ; Wigmore, Evidence § 18 at 338 (3d ed. 1940) and cases cited; McCormick, Evidence 118 (1954) and cases cited.
. McMahon v. Matthews, supra note 12 at 308.
. See, e. g., Baker v. United States, 131 U.S.App.D.C. 7, 36, 401 F.2d 958, 987 (1968).
An essential element entering into the judge’s exercise of discretion is that the central purpose of limiting cross-examination — assuring that evidence is presented in a way which does not confuse the *1175jury, see AVigmore, Evidence §§ 1887-88 (3d ed. 1940) — would not have been thwarted by admission of the evidence in question, for the short trial (2 hours and 17 minutes, including voir dire) did not present any complicated factual issues. AVe note that it is this element which the draftsmen of the Proposed Federal Rules of Evidence have made determinative of the scope of cross-examination. Rule 611 states:
(b) Scope of Gross-Ewamination. A witness may be cross-examined on any matter relevant to any issue in the case, including credibility. In the interests of justice, the judge may limit cross-examination with respect to matters not testified to on direct.
The Advisory Committee’s Note then explains:
The provision of the second sentence, that the judge may in the interests of justice limit inquiry into new matters on cross-examination, is designed for those situations in which the result otherwise would be confusion, complication, or protraction of the case, not as a matter of rule but as demonstrable in the actual development of the particular case.
. See, e. g., New England Newspaper Pub. Co. v. Bonner, 68 F.2d 880 (1st Cir.), cert. denied 292 U.S. 625, 54 S.Ct. 630, 78 L.Ed. 1480 (1934) ; Mills v. Texas Compensation Ins. Co., 220 F.2d 942, 946 (5th Cir. 1955).
. Cf. Davis v. Clark, 131 U.S.App.D.C. 379, 404 F.2d 1356, 1358 (1968) (statement of Tamm, J.) (The requirement in F.R.A.P. 24 that a trial judge state his reasons for denying leave to appeal in forma pauperis “is not onerous if the matter was dealt with in a conscientious manner in passing on the merits.”)
. Contrary to the “fanciful” fears of the dissent that this case “open[s] the door for the open flaunting of the narcotic laws,” we believe that our decision simply assures that appellant’s guilt or innocence will be determined by a jury which has all the relevant information before it.
. In addition, as the government concedes, Turner v. United States, supra, note 2 at 424, 90 S.Ct. 642, requires that we vacate the conviction on the third count of the indictment, which charged a violation of 26 U.S.C. § 4704(a) based on possession of cocaine.