The Controversial Legacy of Justice Clarence Thomas.

Advocacy groups are calling for Supreme Court Justice Clarence Thomas to testify before the Senate Judiciary Committee about his relationship with a GOP donor, but Democrats on the committee have instead called on the Supreme Court to address the issue. Experts warn that calling a sitting justice to testify could escalate conflict between the branches of government and lead to a separation-of-powers showdown. It is rare for Supreme Court justices to testify before Congress voluntarily, and it would be difficult to force Thomas to testify due to the judiciary's constitutional interest in keeping separate from Congress.