dissenting.

I have difficulty with the majority’s conclusion that a remand is necessary in this case because the existence of the sperm slide was disclosed at trial. Dr. Silverstri testified that he examined the vagina for sperm and placed the material on a glass slide. Thus the defendant and his counsel were made aware that a sperm slide had been prepared. Nevertheless, counsel remained silent. He did not demand production of the slide for testing, nor did he request a continuance to review the slide and pursue further discovery.

There is no reversible error for failure to disclose when the information is furnished at trial. See United States v. Agurs, 427 U.S. 97, 103 , 96 S.Ct. 2392, 2397 , 49 L.Ed.2d 342 (1976) (“The rule of Brady v. Maryland ... involves the discovery, after trial, of information which had been known to the prosecution but unknown to the defense.”) (emphasis added); United States v. Iverson, 648 F.2d 737 (D.C.Cir.1981); United States v. Craig, 573 F.2d 455, 492 (7th Cir.1977) cert. denied, 439 U.S. 820 , 99 S.Ct. 83 , 58 L.Ed.2d 110 (1978).

The majority suggests that the sample may have been destroyed prior to Dr. Silverstri’s testimony. If so, this fact was discoverable either by cross-examination, or by a prompt motion to produce. Defense counsel failed to undertake either. 1

*1448 A remand is unnecessary for any of the reasons proffered by the majority. It is clear from the existing record that both the prosecution and the defense had knowledge of the existence of the sperm sample from Dr. Silverstri’s testimony of the existence of the sperm sample. Whether the prosecution is charged with the knowledge that the sample could be used to exculpate the defendant is irrelevant when the defendant knew of its existence at trial and could have reviewed the slide to determine whether in fact it would exculpate him. To remand for a determination of whether a demand by defense counsel for production of the slide would have been successful allows the defendant to have it both ways. If in fact a demand for production would have been futile (because of destruction of the slide), the defendant could have discovered that fact at trial.

A defendant should not be permitted to remain silent when informed of evidence that could conceivably be exculpatory, await the jury’s verdict and then proceed to raise the issue by petition for writ of habeas corpus. See United States v. Kubiak, 704 F.2d 1545, 1552 (11th Cir.1983) (per curiam); Evans v. United States, 408 F.2d 369, 370 (7th Cir.1969).

Moreover, the defense made no showing that the evidence was potentially exculpatory. Apparently only eighty percent of the male population secrete blood in their semen. Hence, for twenty percent of the male population the test of semen to show blood type is not possible. United States v. Kennedy, 714 F.2d 968 at 971 (9th Cir.1983). Hilliard has made no showing that he has the secreter characteristic.

Principally because the sperm slide was made known to counsel and defendant at trial, I do not believe that failure to produce the slide can be made a ground for habeas relief.

. I do not mean to suggest here that defense counsel was incompetent. The magistrate states in his recommendation, "A review of the record indicates that petitioner was vigorously defended by counsel and counsel’s actions clearly were at or beyond the level of reasonable competence.”