Appellant was convicted in July, 1965, on four counts of assault and one count of carrying a pistol without a license. He was given concurrent sentences the longest of which was 4 to 12 years. All the alleged crimes related to an apparent attempt to rob a tourist home about 4:00 a. m. on March 28, 1965, when the night manager, Samuel Brown, was assaulted. The only evidence tending to connect appellant with the crimes was Brown’s identification of him. Appellant not only challenged the identification but, with three friends, testified to an alibi, to the effect that he was in a party at a friend’s house when the crimes were committed.
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Appellant and two other witnesses, Mrs. McCoy and Mr. Griffis, all testified the party was on the night of March 27-28. None of these three witnesses said they did not remember the date or that it was the Saturday preceding appellant’s arrest. Another defense witness, Sirs. Smith, said “I do not remem*885ber it was exactly March 28 but I knew it was the Saturday prior to his arrest.” But it is not clear that she meant the last Saturday “prior to his arrest”, for she had just testified: “Well, maybe I am not sure it was the 28th but I know it was a Saturday before he was arrested * * # ”
In his closing argument the prosecutor said: “The witnesses told you, two or three of them I asked, — I don’t think I asked the criminal — the person on probation [Griffis was on probation] * * * The other witnesses testified as to this party, that they didn’t remember on what date it was. They didn’t remember that it was on March 28th, but the way they fixed the date was that the party was the Saturday preceding the arrest, because when they found out he was arrested, they remembered that he had been at a party * * * the Saturday night preceding that.” As the prosecutor pointed out, the Saturday immediately preceding appellant’s arrest was not March 28, the date of the crime, but a week later.
The prosecutor’s erroneous account of the alibi testimony was highly prejudicial. The witnesses placed the defendant at a party at the time of the crime. The prosecutor’s garbled version of their testimony did not. His misstatements made the difference between a strong alibi and no alibi. If, but only if, the jury relied on his misstatements, it could find the defendant guilty without rejecting as untrue the witnesses’ stories about the defendant’s presence at the party. The Government’s case was not particularly strong. And it “is generally held that whether improper conduct of Government counsel amounts to prejudicial error depends, in good part, on the relative strength of the Government’s evidence of guilt.” Jones v. United States, 119 U.S.App.D.C. 213, 214 n. 3, 338 F.2d 553, 554 n. 3 (1964). But for the prosecutor’s misstatements, the jury might well have found that the alibi testimony created a reasonable doubt.
Appellant’s counsel had already objected to the prosecutor’s giving the jury his version of Mrs. Smith’s testimony and had asked that her testimony be transcribed. After the jury retired it asked to hear her statements and Mrs. McCoy’s. The judge refused these requests and did nothing to correct the prosecutor’s error. “In these circumstances prejudice to the cause of the accused is so highly probable that we are not justified in assuming its non-existence.” Berger v. United States, 295 U.S. 78, 89, 55 S.Ct. 629, 633, 79 L.Ed. 1314 (1935). Jones v. United States, 119 U.S.App.D.C. 213, 338 F.2d 553 (1964) ,1 We must therefore reverse the conviction.
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tS] Because a similar question is likely to arise in a new trial, we add that we think the judge should have granted the motion to examine Brown’s grand jury testimony in camera. This should be done when a principal prosecution witness has made conflicting statements indicating the possibility of an inconsistency between his trial testimony and his grand jury testimony. Harrell v. United States, 115 U.S.App.D.C. 169, 170 n. 5, 317 F.2d 580, 581 n. 5 (1963); Simmons v. United States, 113 U.S.App.D.C. 369, 308 F.2d 324 (1962); De Binder v. United States, 110 U.S.App.D.C. 244, 292 F.2d 737 (1961). Also, it should be done when the Government’s case rests upon the contradicted testimony of a single witness. Gordan v. United States, 112 U.S.App.D.C. 33, 299 F.2d 117 (1962). Worthy v. United States, 122 U.S.App.D.C. 242, 352 F.2d 718 (1965), cert. filed 1/5/66, is distinguishable because there a defense witness corroborated the prosecution witness’s testimony. After examination, the court should reveal to counsel any inconsistency that is not plainly immaterial. See De Binder v. United States, Gordan v. United States, and Simmons v. United States, supra.
Reversed and remanded for a new trial.
. In Cross v. United States, 122 U.S.App.D.C. 283, 353 F.2d 454 (1965), because a prosecutor’s erroneous statement caused no “substantial prejudice” we affirmed a conviction. The prosecutor’s mistake there was in saying that both the defendant’s accomplices stated they received no promises from law enforcement ofeials, whereas in fact only one had so stated; the other had said that officials promised to “ ‘see what they could do’ ” if she would cooperate with them, and the charges against her were dropped. There the prosecutor’s mistake, though substantial, was relatively minor. If the jury believed the prosecutor’s erroneous statement, the defendant’s case was not weakened and the government’s case was not greatly strengthened; only the weight of one government witness’s testimony was affected; whereas in our case, the prosecutor’s misstatement, if believed, wiped out a strong alibi which, but for the defendant’s own testimony, was his entire case. The government’s evidence was stronger in Cross than here and it does not appear that the defendant’s was as strong there as here. Here, the only evidence that tended to connect the defendant with the crimes was one witness’s identification of him, while in Cross the testimony of two accomplices was supported by “an admittedly weak identification of appellant by a priest at the robbed church, and testimony by owners of two tourist homes that some hours after the robbery, during the same night, appellant and his accomplices checked into a tourist home, cheeked out, and then checked into another tourist home for the remainder of the night.” 353 F.2d at 455 n. 1. And counsel in Cross, unlike counsel in this case, did not object to the prosecutor’s giving the jury his version of the witness’s testimony and did not ask that the testimony be transcribed.