The Los Angeles Times reports that Supreme Court Justice Clarence Thomas failed to disclose his Tea Party activist wife’s six-figure income from the right wing Heritage Foundation for at least five years, a possible violation of the laws governing federal judges.

A Supreme Court spokesperson could not be reached for comment late Friday. But Virginia Thomas’ employment by the Heritage Foundation was well known at the time.

Virginia Thomas also has been active in the group Liberty Central, an organization she founded to restore the “founding principles” of limited government and individual liberty.

In his 2009 disclosure, Justice Thomas also reported spousal income as “none.” Common Cause contends that Liberty Central paid Virginia Thomas an unknown salary that year.

Federal judges are bound by law to disclose the source of spousal income, according to Stephen Gillers, a professor at NYU School of Law. Thomas’ omission — which could be interpreted as a violation of that law — could lead to some form of penalty, Gillers said.