The relator-appellant Castillo was tried and convicted by a jury in a New York state court for the unlawful sale of heroin. He was sentenced to imprisonment for a period of from five to six years. The judgment was affirmed on appeal. People v. Castillo, 16 A.D.2d 235, 226 N.Y.S.2d 785 (1st Dep’t) (3-to-2 decision), aff’d mem., 12 N.Y.2d 732, 186 N.E.2d 198, 233 N.Y.S.2d 938 (1962). State court remedies were exhausted by the denial by another New York court of a petition for a writ of habeas corpus. A petition in the federal district court was *401denied on the basis of the trial transcript and other state court records. We affirm.
Two issues were raised and rejected below and are renewed on appeal: (1) whether the prosecutor’s trial conduct and his summation before the jury in the state court deprived Castillo of a fair trial in violation of the due process clause of the Fourteenth Amendment; and (2) whether Castillo’s rights under the Fourth and Fourteenth Amendments were violated by reference at his trial to evidence found in the course of a search which, it is claimed, was illegal under the rule of Mapp v. Ohio, 367 U.S. 643, 81 S.Ct. 1684, 6 L.Ed.2d 1081 (1961).
I.
We have considered each of the points made by appellant as to the conduct of the prosecutor at the trial. The weightiest of these points concerns the prosecutor’s remark in his summation concerning the principal government witness;
“The issue in this case is very important, but it is a relatively simple issue: Is Detective Schiano a liar, or is he truthful? If he is telling the truth, then it is your sworn obligation to convict. If he is a liar, then you must acquit. By your verdict you will judge whether Detective Schiano is an honest, faithful, courageous public servant, or whether he is a perjurer and a cheat who does not belong on the police force or does not belong in any public service.” 16 A.D.2d at 237-238, 226 N.Y.S.2d at 788.
The language distorts the issues of the trial and is therefore offensive to the proper conduct of the trial. It can hardly be excused, as is argued, by remarks of defendant’s counsel which are called “provocative.” The prosecutor’s remarks should not have been made and the New York Appellate Division, which divided three to two on the point, might well have been justified in ordering a new trial.
But whatever error the state court may have committed in failing to grant a new trial, the defect in the trial did not attain constitutional proportions. The prosecutor’s conduct did not create a situation so prejudicial to appellant that he was denied a fair trial within the meaning of the due process clause of the Fourteenth Amendment.
“The speeches of counsel for defendants apparently provoked statements by the District Attorney of which petitioners now complain. This does not raise a due process question.
“As we have recently said, ‘it is not asking too much that the burden of showing essential unfairness be sustained by him who claims such injustice and seeks to have the result set aside, and that it be sustained not as a matter of speculation but as a demonstrable reality.’ ” Buchalter v. New York, 319 U.S. 427, 431, 63 S.Ct. 1129, 1132, 87 L.Ed. 1492 (1943), quoting Adams v. U. S. ex rel. McCann, 317 U.S. 269, 281, 63 S.Ct. 236, 87 L.Ed. 268 (1942).1
Conduct of state prosecutors which it was contended was unfair and prejudicial has consistently been held on collateral attack in the federal courts to fall short of constituting a lack of due process. See, e. g., Burwell v. Teets, 245 F.2d 154, 168 (9th Cir.), cert. denied, 355 U.S. 896, 78 S.Ct. 271, 2 L.Ed.2d 194 (1957); United States ex rel. Burke v. Denno, 243 F.2d 835 (2d Cir.), cert. denied, 355 U.S. 849, 78 S.Ct. 76, 2 L.Ed.2d 58 affirming 148 F.Supp. 498 (S.D.N.Y.1957); Sampsell v. People of State of California, 191 F.2d 721 (9th Cir. 1951), cert. denied, 342 U.S. 929, 72 S.Ct. 369, 96 L.Ed. 692 (1952). See, *402however, Pike v. Dickson, 323 F.2d 856, 858 n. 3, 860-861 (9th Cir. 1963) cert. denied, 377 U.S. 908, 84 S.Ct. 1164, 12 L.Ed.2d 179 (1964).
II.
Petitioner’s second point relates to the admission of testimony concerning material found in a search of Castillo’s room. The State does not contest the claim that the search was conducted in violation of Castillo’s Fourth and Fourteenth Amendment rights. The issue is whether, where a state court judgment is collaterally attacked in a federal court, the rule of Mapp v. Ohio, supra, is properly applicable to a situation in which the admissibility vel non of the challenged evidence is so close a question as to render the correctness of either answer extremely doubtful. We believe that if we are to upset a state conviction on constitutional grounds we ought to be able to find a more robust basis for doing so than the present case affords.
At the state court trial on direct examination of a police officer the following took place:
“Q. [by the prosecutor] Did you search the apartment? A. Yes, we gave it a search.
“Q. Did you find anything? A. Yes.
“[Prosecutor] * * *: Your witness.”
Relator argues that by this exchange the prosecutor left the jury to infer that incriminating evidence had been found and put defense counsel in the difficult position of either moving to strike the testimony or eliciting from the witness exculpatory testimony that might allay the jury’s suspicions.
Defense counsel thereupon asked on cross-examination whether narcotics were found, to which question the answer was negative.
On redirect the prosecutor, over defendant’s objection, brought out that in the course of the search a wire clothes hanger and a silk stocking, instruments used in cutting narcotics, were found. The trial judge ruled on defendant’s objection that defense counsel had “opened the door” by asking whether narcotics had been found.
On this appeal the appellant argues that, since it was the prosecutor’s tactics which made it necessary for the defense to ask the question as to the search, the question did not have the effect of opening the door to the prosecution for introducing further evidence on the search and that the introduction of such evidence violated appellant’s rights under the rule of the Mapp case.
Although we would affirm on this very narrow issue of “who opened the door?”, Walder v. United States, 347 U.S. 62, 74 S.Ct. 354, 98 L.Ed. 503 (1954); United States v. Rivera, 346 F.2d 942 (2d Cir. June 11, 1965), the question is a very close one, as the strength of the dissent’s arguments indicates.
It should be noted that at the time of Castillo’s trial in April 1961 illegally seized evidence could still be admitted in the state court under Wolf v. Colorado, 338 U.S. 25, 69 S.Ct. 1350, 93 L.Ed. 1782 (1949). The prosecutor did not bring up the search in knowing violation of Castillo’s constitutional rights, since Mapp v. Ohio, supra, was not decided until June 1961. Indeed, the Mapp rule is applicable to Castillo’s case only because the final decision of his appeal postdated the decision in Mapp. See Linkletter v. Walker, 85 S.Ct. 1731, p. 1734 n. 5 (1965).
We do not believe that the purpose of the exclusionary rule of Mapp v. Ohio is well served by holding in such a doubtful case and on collateral attack, that constitutional rights have been infringed, when the contention on which the holding is based has been rejected in the trial court, two state appellate courts, and the federal district court. Where the issue of whether or not the fruits of an illegal search can be used turns on whether the prosecutor overstepped the bounds of a subsequent appellate decision, or wheth*403er the tactics of opposing counsel gave him leave to do so, the police are not likely to be deterred in taking the chance of finding useful evidence by an illegal search.
It is the duty of the federal courts to vindicate, where necessary by habeas corpus relief, federal constitutional rights; it is not, however, our function to supervise state courts in the procedure by which those rights are judicially administered unless the procedure and rules applied in the state court are so fundamentally unfair as to undermine the federal guarantee.2 Where as in this case, the error, if any, is a highly technical error of local trial practice, it would seem an inappropriate occasion for the exercise of the power of the Great Writ.
In United States v. Guerra, 334 F.2d 138, 146 (2d Cir.), cert. denied, 379 U.S. 936, 85 S.Ct. 337, 13 L.Ed.2d 346 (1964), we said:
“The day has certainly not come when courts will set a convicted criminal free for no reason other than that some practice of police or prosecution — wholly unrelated to the conviction itself — did not meet with their approval. If that unhappy day should ever arrive, the often-heard criticism that law and lawyers are interested only in ‘technicalities’ will have a ring of truth, and courts may rightfully be accused of exalting form above substance.”
See United States ex rel. Townsend v. Ogilvie, 334 F.2d 837, 843-844 (7th Cir. 1964).
Affirmed.
. For a discussion of the summation complained of see People v. Buchalter, 289 N.Y. 181, 228-230, 45 N.E.2d 225, 249-250 (1942) (Lehman, J., concurring), aff’d, 319 U.S. 427, 63 S.Ct. 1129, 87 L.Ed. 1492 (1943).
. The standards by which we determine on direct review of federal criminal trials whether an objection to the admissibility of improper evidence has been waived by the objectant’s prior use of similar testimony have been set forth in United States v. Beno, 324 F.2d 582, 588-589 (2d Cir. 1963). As we said, in reversing a federal criminal conviction:
“[I]t makes little sense to insist that once incompetent evidence is erroneously admitted, the error must of necessity be compounded by ‘opening the door’ so wide that rebutting collateral, inflammatory and highly prejudicial evidence may enter the minds of the jurors. In short, a small advantage improperly obtained does not compel the exaction of a gross disadvantage in penaty, particularly where a tarnished verdict is the inevitable result.” IMH.
See generally 1 Wigmore, Evidence § 15 (3d ed. 1940 & 1964 Pocket Supp.).