There's no audio on the video, but police officers appear to be laughing as they clean Dent's blood off their uniforms.
Dent says he was in the room, just off camera, and heard the police laughing at him.
At one point in the video, an officer is seen lying down on a bench, appearing to imitate Dent during the arrest.
Dent's attorney says Dent suffered a number of injuries including a closed head injury and broken ribs, but had not been allowed to see a doctor.
The beating and arrest in late January was caught on police dash cam video. Dent admitted to running a stop sign that initiated the arrest but says police went too far, and says even cocaine was planted in his vehicle to get the charges.
Drug charges against the 57-year-old were officially dropped last week in Wayne County. Former Inkster police officer William Melendez has also been charged with crimes related to Dent's arrest and beating.