MEMPHIS, Tenn. (AP) — A pile of stuffed animals marks the spot where 15-year-old Justin Thompson fell, fatally shot by an off-duty Memphis police officer on a school night in a working-class neighborhood.

The Sept. 24 shooting is still under investigation, but the question of whether Officer Terrance Shaw used excessive force makes the case one more example for critics who say there is a years-long culture of misconduct in the police department of Tennessee's largest city.

This year, at least 23 Memphis officers and civilian personnel have been charged with crimes, from DUI and drug dealing to human sex trafficking. Going back to 2004, dozens of officers in the 2,400-officer force have been charged with corruption.