A Republican congressman is demanding to know why Attorney General Merrick Garland is taking a hard pass on prosecuting a left-wing loudmouth who threatened his family. Indiana GOP Rep. Jim Banks sent Garland a letter asking why the feds refused to go after a suspect named Aaron Thompson. The threats occurred in 2023, and Banks reportedly sent the letter in December. But he made it public this week after Garland defended the Justice Department’s crime-fighting techniques in a Washington Post opinion article last week. Read: Keeping Trump Under Gag Order Likely Violates His, And Americans, Righ…