The House Jan. 6 select committee's year-long effort to get former Trump chief of staff Mark Meadows to testify, along with other unwilling witnesses, has exposed the limits of Congress' subpoena power. Despite winning a court fight to defend its subpoenas and voting to refer Meadows for prosecution of contempt of Congress, Meadows never testified about the emails and texts he exchanged with members of Congress in the days surrounding the Jan. 6, 2021, attack on the Capitol. The Justice Department also declined to charge him.

Experts say that this episode illustrates the difficulty congressional investigations face in enforcing subpoenas alone, and a lack of consequences for unwilling witnesses may haunt future congressional investigations. While committee members and Justice Department lawyers have pointed to court victories as a vindication of congressional investigative power, the slow-moving courts create a practical issue that hangs over all of this. Congress can issue subpoenas, but it needs court enforcement.

The Jan. 6 committee's experience highlights the limitations of civil contempt and inherent contempt, two powerful tools to enforce subpoenas. Civil contempt is undermined by the same slow-moving courts, and inherent contempt, where Congress arrests defiant witnesses to try to force their testimony, lacks political will. The legal record exposed by the Jan. 6 committee's subpoenas shows how much the legislative branch will rely on the courts and federal agencies in future probes.