A shirtless 15-year-old boy with no arms and no legs was held facedown on the kitchen floor of his Arizona group home by a deputy more than twice his size, an eight-minute video released last week shows.

The teenager was arrested and later charged with disorderly conduct, his lawyer said. That prompted him to release the video to a local TV station, which published the footage on Wednesday. By the next day, prosecutors had dropped the charge, and the deputy, Manuel Van Santen, was put on administrative leave on Friday.

Sheriff Mark Napier of Pima County said he authorized a criminal investigation into Deputy Van Santen’s conduct. He called the video “shocking” and “personally saddening to watch” in a statement released Monday.

“It’s a horrible spectacle,” said Joel Feinman, the teenager’s lawyer. “He was assaulted by a man with a badge and a gun, just screamed and cursed at.”