18 U.S.C. §1014 states in part:
Sec. 1014. Loan and credit applications generally; …
Whoever knowingly makes any false statement or report, or willfully overvalues any land, property or security, for the purpose of influencing in any way the action of the …[any governmental agency, lender, bank, credit union, corporation, etc.] … upon any application, advance, discount, purchase, purchase agreement, repurchase agreement, commitment, or loan, or any change or extension of any of the same, by renewal, deferment of action or otherwise, or the acceptance, release, or substitution of security therefore, shall be fined not more than $1,000,000 or imprisoned not more than 30 years, or both.

The following is re-printed with permission from the 2003 – 2004 Real Estate Update Course
published by the North Carolina Real Estate Commission.

This is all that needs to be said concerning those who try to pressure the appraiser to overvalue a property, or those appraisers who become complicit in such action by “hitting the mark” when the mark is above market value. Note: this is only one of several federal statutes that address this issue, with the same penalty. Letting your client know the risk being taken by all involved in such scheme may relieve some of the pressure.

This is also cited in the NCPAC June 2007 issue of "The Scope"

Article "Federal Penalties for Overvaluing Real Estate" by Doug Winner, NCPAC President-Elect The Scope, Volume 3, Issue 3, May / June 2007, Page 6 (cache copy)