As for Clarence Thomas, he did not proclaim his innocence. He simply, over and over, stated that his wife had no non-investment income--even though she was receiving hundreds of thousands of dollars from conservative advocacy groups.
One of the best articles I've seen on 18 U.S.C. 1001 makes it clear that Thomas almost certainly violated the law. Prosecutors unquestionably have probable cause to bring charges. The crime boils down to "an untrue statement knowingly made with the intent to mislead." And it includes written statements, such as those Thomas made on his financial-disclosure form, marking "none" for his wife's non-investment income.
What would prosecutors need in order to prove the case against Thomas? From the article:
Case Law Interpreting Section 1001
The elements that the Government needs to prove in prosecuting a case under section 1001 are
1) a statement is made
2) the statement is false
3) materiality
4) specific intent, and
5) agency jurisdiction. United States v. Gilbertson, 588 F.2d 584, 589 (8th Cir. 1978).
From where we sit, all of those elements appear to be in place.
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