Appellant was convicted of interstate transportation of a stolen vehicle. He contends that the evidence was insufficient to prove a violation of the statute, 18 U.S.C. § 2312; that his statement to an F.B.I. agent was erroneously admitted; and that the prosecution improperly commented on his failure to take the stand.1 The record does not support these contentions.
I.
The owner of a 1962 Chevrolet left his car in a parking lot in St. Louis, Missouri, at about 8:00 o’clock A.M. on March 6, 1969. Except his wife, no one else was authorized to drive the car. Appellant was arrested about six hours later while driving the car in Madison, Illinois.2 The next morning in response *930to questioning by an F.B.I. agent, appel-lent acknowledged that he had been in the car when it crossed the state line, and that he knew the car was stolen. These facts are sufficient to prove him guilty of interstate transportation of a stolen vehicle.3
Appellant’s challenge to the sufficiency of the evidence is predicated on a portion of his statement to the F. B.I. agent. He told the agent that he was merely a passenger when the car crossed the state line; and that before entering the car he did not know that it had been stolen. Nevertheless, by offering the statement into evidence the prosecutor did not vouch for the accuracy of the entire document. Epps v. United States, 81 U.S.App.D.C. 244, 157 F.2d 11, 12 (1946); United States v. Cindrich, 140 F.Supp. 356, 359, 360 (W.D. Pa.1956) affirmed 241 F.2d 54 (3rd Cir. 1957). Considering the evidence as a whole, the jury was free to discredit the exculpatory portion of the statement.4 Accordingly, unlike the cases on which appellant relies, we are not faced with the problem of differentiating between an innocent passenger and an active participant in an interstate journey. See Lawrence v. United States, 400 F.2d 624 (9th Cir. 1968); Baker v. United States, 395 F.2d 368 (8th Cir. 1968). The guilty verdict was adequately supported by the evidence.
II.
Appellant’s claim that his statement was coerced is predicated on the fact that he had been in custody for almost 22 hours before he was interviewed by the F.B.I. agent. Relying on the Mc-Nabb-Mallory doctrine5 as embodied in Rule 5(a) of the Federal Rules of Criminal Procedure, he contends that he should have been taken before a commissioner or other judicial officer before he was questioned by the agent. A review of what actually happened, as disclosed by the record, demonstrates that appellent’s rights were fairly protected.
The arrest in the early afternoon of March 6 was by local police on a state charge.6 The following day he was committed to the Vandalia State Penal Farm for a period of six months.7 On that morning, the desk sergeant at the Madison police station telephoned the *931F.B.I. to report that appellant had been arrested in possession of a stolen car.8 The F.B.I. agent arranged to interview appellant at the Madison police station before he was removed to Vandalia. He was not then in federal custody; he was not arrested for the federal offense until six months later when he was discharged from state custody.
After his indictment in September, appointed counsel moved to suppress the statement. Appellant acknowledged that he had executed a written waiver of rights, but testified that he was under the influence of drugs at the time. This testimony was somewhat inconsistent with the fact that he had been in state custody for about 22 hours before his interview. Moreover, appellant acknowledged that two weeks later, while he was at Vandalia, he had voluntarily written a letter to the F.B.I. in which he asked for a “break” and reconfirmed a portion of his statement. That letter contained no reference to any unfair treatment or to any drugs. In the circumstances, the trial judge was entitled to accept the F. B.I. agent’s testimony and to find that appellant’s statement and waiver of rights were voluntary.
Unlike the position taken in the trial court at the hearing on the motion to suppress, appellant now argues that the statement was inadmissible as a matter of law because he had been in custody for about 22 hours without having been taken before a judicial officer before he was interviewed. As this argument was not advanced below, the record does not tell us what advice, if any, appellant may have received from a state judicial officer. But even if he received none, it was permissible for the F.B.I. agent to question him while he was in state custody. Since he was adequately advised of his rights, and there is no reason to find that the interview was conducted under coercive circumstances, it was not error to receive the statement in evidence.
Rule 5(a) prescribes the procedure to be followed when a suspect is taken into federal custody.9 Appellant was not arrested on the federal offense until six months after he made his statement; he was then taken before a commissioner “without unnecessary delay,” as required by the rule. Nor is there any basis in this record for regarding appellant’s state custody as merely “nominal” or the result of the kind of “working arrangement” between state and federal officers which gave rise to Anderson v. United States, 318 U.S. 350, 352, 355-356, 63 S.Ct. 599, 87 L.Ed. 829. Cf., United States v. Broadhead, 413 F.2d 1351, 1358-1359 (7th Cir. 1969).10
Finally, there is no evidence that the questioning itself was unreasonably prolonged or persistent. It was not merely a continuation of prior interrogation by local police officers, cf., Westover v. United States, 384 U.S. 436, 494-497, 86 S.Ct. 1602, 16 L.Ed.2d 694, and there is no evidence that the questioning was conducted improperly or under coercive conditions. In our opinion .the mere fact that appellant had been in state custody for about 22 hours does not require exclusion of his statement.
*932III.
Appellant contends that the prosecutor committed “plain error” by commenting on his failure to testify.11 The specific comment challenged by appellant was included in the rebuttal argument. It should be read in context.
In the prosecutor’s principal closing argument he emphasized the inference of guilt that resulted from possession.of a recently stolen vehicle “unless such possession is explained or accounted for on the date in question in some way consistent with innocence.” 12 In response, appellant’s counsel argued that the exculpatory portion of the statement given to the F.B.I. agent accounted for his possession of the car at the time of his arrest consistently with his innocence. Thereafter, in rebuttal, the prosecutor argued:
“As far as I’m concerned, we can throw the admission out, and the Government right off the bat has a pretty •good case. In fact, we have a pat case as far as I’m concerned.
“We have the stolen car, and we have the interstate transportation, and we have the Defendant picked up in the car.
“And again by that instruction that I mentioned to you, again there has been no evidence to his innocence, and you can infer his guilt just from that alone.”
A comment on defendant’s failure to testify would violate the Fifth Amendment, Griffin v. California, 380 U.S. 609, 85 S.Ct. 1229, 14 L.Ed.2d 106, as well as the statute, now 18 U.S.C. § 3481, modifying the common law rule that an accused could not testify in his own behalf, Wilson v. United States, 149 U.S. 60, 13 S.Ct. 765, 37 L.Ed. 650. In those cases the prosecutor argued, in substance, that an innocent man would have taken the stand to deny or explain the evidence against him,13 and that the failure to do so was itself proof of guilt.14 No such argument was made in this case.
In order for the prosecutor to obtain the benefit of the presumption that arises from unexplained possession of a stolen vehicle, it is appropriate argument to point out that the possession has not been adequately explained, or, if *933no explanatory evidence has been offered, to point out that the government’s case is uncontradict.cd. That is the nature of the prosecutor’s rebuttal argument.
It did not ask the jury to infer guilt from his failure to testify. On the contrary, it asked the jury to draw inferences properly arising from the government’s affirmative evidence. We are not unmindful that reference to the fact that the prosecution’s affirmative case is uncontradieted may remind the jury that the defendant elected not to testify. But that election is almost certain to prejudice the defense no matter what else happens in the courtroom. The importance of minimizing that prejudice does not outweigh the necessity for preserving otherwise fair and accepted procedures. It is one thing to accord respect to an accused’s constitutionally protected privilege to refuse to testify by forbidding prosecutorial comment on its exercise; it is quite another to contend, as appellant does here, that his assertion of the privilege has provided him with an affirmative benefit by depriving the prosecutor of the full value of a presumption that arises from unexplained evidence of guilt. We hold that the prosecutor’s comment was proper.
The judgment is affirmed.