Multiple investigations into the Jan. 6 attack on the U.S. Capitol have homed in on a single provision in the federal crime code: 18 U.S.C. § 1512 (c)(2)—obstruction of an official proceeding.

It’s the most common felony charge against those accused of breaching the Capitol, lodged against roughly 275 Jan. 6 defendants. Several judges in the federal court in Washington, D.C., have recently upheld the DOJ’s use of that statute in the Jan. 6 investigation.