26 U.S.C. § 7205

1. (a)Any individual required to supply information to his employer under section 3402 who willfully supplies false or fraudulent information, or who willfully fails to supply information thereunder which would require an increase in the tax to be withheld under section 3402, shall, in addition to any other penalty provided by law, upon conviction thereof, be fined not more than $1,000, or imprisoned not more than 1 year, or both.
2. (b)If any individual willfully makes a false certification under paragraph (1) or (2)(C) of section 3406(d), then such individual shall, in addition to any other penalty provided by law, upon conviction thereof, be fined not more than $1,000, or imprisoned not more than 1 year, or both.