Supreme Court Justice Clarence Thomas failed to report his wife's income from a conservative think tank on financial disclosure forms for at least five years, the watchdog group Common Cause said Friday.
Between 2003 and 2007, Virginia Thomas, a longtime conservative activist, earned $686,589 from the Heritage Foundation, according to a Common Cause review of the foundation's IRS records. Thomas failed to note the income in his Supreme Court financial disclosure forms for those years, instead checking a box labeled "none" where "spousal noninvestment income" would be disclosed.
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.
"It wasn't a miscalculation; he simply omitted his wife's source of income for six years, which is a rather dramatic omission," Gillers said. "It could not have been an oversight."
But Steven Lubet, an expert on judicial ethics at Northwestern University School of Law, said such an infraction was unlikely to result in a penalty. Although unfamiliar with the complaint about Thomas' forms, Lubet said failure to disclose spousal income "is not a crime of any sort, but there is a potential civil penalty" for failing to follow the rules. He added: "I am not aware of a single case of a judge being penalized simply for this."
The Supreme Court is "the only judicial body in the country that is not governed by a set of judicial ethical rules," Gillers said.
A spokesman for the Administrative Office of the U.S. Courts, which oversees the financial disclosures, could not be reached Friday night to comment on what actions could be taken. In most cases, judges simply amend their forms when an error is discovered.
"Without disclosure, the public and litigants appearing before the court do not have adequate information to assess potential conflicts of interest, and disclosure is needed to promote the public's interest in open, honest and accountable government," Common Cause President Bob Edgar wrote in a letter to the Judicial Conference of the United States.
The allegation comes days after Common Cause filed a letter requesting that the Justice Department investigate whether Justices Thomas and Antonin Scalia should have disqualified themselves from hearing a campaign finance case after they reportedly attended a private meeting sponsored by Charles and David Koch, billionaire philanthropists who fund conservative causes.
In the case, Citizens United vs. Federal Election Commission, the court ruled that corporate and union funds could be spent directly on election advertising.
The Koch brothers have been key supporters of the group Americans for Prosperity, which spent heavily in the 2010 midterm election and claims a nonprofit tax status that allows it to avoid disclosing its donors.
Clarence Thomas has been the lone justice to argue that laws requiring public disclosure of large political contributions are unconstitutional.
A Supreme Court spokesperson later said that Thomas dropped by the private event, but that Scalia did not attend.
Tom Hamburger in the Washington bureau contributed to this report.