Editor’s note: Some of the money used to organize the Jan. 6 pro-Trump “March to Save America” came from social welfare groups. One of them, Women for America First, notably obtained a permit from the National Park Service for the rally – which preceded an assault on the Capitol in which at least five people died. The Conversation U.S. asked nonprofit law scholar Ellen Aprill, who served in the Treasury Department’s Office of Tax Policy in the late 1980s, about possible ramifications for these nonprofits.