Schmaderer says three more officers have been put on leave and another has been reassigned. Their names haven't been released.
The March 21 incident was secretly recorded by a neighbor. The officers were responding to an on-going parking complaint in the north Omaha neighborhood.
Schmaderer ordered an internal investigation a day after the video turned up online. It showed an officer grabbing 28-year-old Octavius Johnson from behind, violently throwing him to the ground and punching him while he was restrained.
The chief assumed responsibility for any future criticism in the handling of the incident.
"These are my findings to date. I stand by my decisions, and any criticism leveled after today should be focused directly onto me."