Nice exposition of the elements of an 18 USC 1001 violation – lying to a federal agent, or in this case, Congress, in this article in the Washington Post. Did Jeff Sessions violate the law in his confirmation hearing by denying contact with the Russians? As the article explains, prosecutors have brought charges in cases involving far more trivial misstatements and situations far less consequential than whether a nominee to be the nation’s chief law enforcement officer misled fellow senators during his confirmation hearings.