The Orlando police report shows 55-year-old Willie L. Buie was charged with resisting arrest with violence during Tuesday night's game. Celtics spokesman Jeff Twiss confirmed it was Daniels' stepfather.
Officers responded to a disturbance in a lower-level section during the second half. Police say they tried to escort Buie from his seat, but he refused, using expletives at officers and swinging his arms free.
He eventually was escorted out near a security office but kept his hands under his body to avoid handcuffs. That's when police say an officer used a stun gun on Buie's back for about 5 seconds.
The report did not say exactly what prompted officers to remove Buie from his seat. A message seeking comment at the number listed for Buie on the police report was not immediately returned.
Daniels briefly left the Celtics bench and returned to the locker room area during the second half, but quickly returned during a TV timeout.
Members of Daniels' family were spotted outside the locker room folllowing the game, but Daniels was not present when the room opened to the media.
Daniels, 29, grew up in the Orlando area. He later went to Auburn and is in his seventh NBA season. Daniels has been used sparingly during the playoffs.
Boston won 95-92 on Tuesday night to take a 2-0 series lead.
The incident is the latest in recent weeks involving police using a stun gun when arresting a fan during a sporting event.
A Philadelphia police officer used a stun gun on a teenager dashing through the outfield during a Phillies game earlier this month. A few days later, a man attending the second round of The Players Championship golf tournament in Ponte Vedra Beach, Fla., was subdued with a stun gun after he resisted arrest for disorderly intoxication.
Chris Forsberg of ESPNBoston.com contributed to this report.