CLEVELAND, June 13 -- When more than a hundred FBI agents descended on the offices of the Ohio Organizing Collaborative and the homes of its staff this week, the Trump administration was not so much investigating a crime as it was sending a message. The target was a grassroots group whose offense, in the eyes of a Justice Department remade in the president's image, appears to be the simple act of helping Ohioans register to vote. Five months before the midterm elections, the raid reads less like law enforcement and more like intimidation dressed up in a search warrant.

Federal agents searched the group's Cleveland headquarters on Thursday, seizing computers and laptops while colleagues fanned out across Ohio to question staff members and...