man Walter’s agent, announcing the results of the Committee’s deliberations. And so far as he knew, the Committee, when it initially decided to hold a public hearing, did so in accordance with Rule IV. It was not until petitioner’s trial, when his attorney for the first time had an opportunity for searching examination, that it became apparent the Committee was violating its rules.
It may be assumed that if petitioner had expressly rested his refusal to answer upon a violation of Rule IV and the Committee nevertheless proceeded, he would be entitled to acquittal, were he able to prove his defense. Otherwise, if Yellin could be convicted of contempt of Congress notwithstanding the violation of Rule IV, he would be deprived of the only remedy he has for protect-. ing his reputation. Certainly the rights created by the Committee’s rules cannot be that illusory.
Of course, should Yellin have refused to answer in the mistaken but good-faith belief that his rights had been violated, his mistake of law would be no defense. Watkins v. United States, 354 U. S. 178,208; Sinclair v. United States, 279 U. S. 263, 299. But he would at least be entitled to submit the correctness of his belief to a-court of law.
Yellin should be permitted the same opportunity for judicial review when he discovers at trial that his rights have been violated. This is especially so when the Committee’s practice leads witnesses to misplaced reliance upon its rules. When reading a copy of the Committee’s rules, which must be distributed to every witness under Rule XVII, the witness’ reasonable expectation is that the Committee actually does what it purports to do, adhere to its own rules. To foreclose a defense based upon those rules, simply because the witness was deceived by the Committee’s appearance of regularity, is not fair.