District Attorney Chesa Boudin has launched a criminal investigation into a San Francisco sheriff’s deputy seen shoving a protester from behind in a video posted to social media.

The footage appears to show the deputy using a baton to shove a protester from the sidewalk onto the ground near Pine and Davis streets during George Floyd demonstrations.

The demonstrator is then seen flipping onto his back with his hand up as the deputy continued to push protesters away from a law enforcement vehicle parked on the curb.

In a tweet Wednesday, Boudin said the incident occurred May 31 at around 5:03 p.m. His office has not released further information on the charges the deputy could face.

On May 31, at appx 5:03 PM, a BLM protester was shoved to the ground by a member of the SF Sheriff's Dept. My office has opened a criminal investigation. If anyone has relevant video/can identify the suspect/witnesses/victims in the video below, email districtattorney@sfgov.org https://t.co/zTsW606eni

— Chesa Boudin 博徹思 (@chesaboudin) June 10, 2020

Sheriff Paul Miyamoto has launched an administrative investigation into the incident but said the use of force in the video did not appear to be criminal.

“Initial review of available information and circumstances does not appear to rise to criminal conduct,” Miyamoto said.

A spokesperson for the department declined to release the name and rank of the deputy involved.

But the deputy is not believed to be a member of the San Francisco Deputy Sheriffs’ Association, which represents deputies and senior deputies, according to the union.

Capt. Lisette Adams, head of the San Francisco Sheriff’s Managers and Supervisors Association, said she had yet to review the case and could not confirm the identity of the member.

That union represents sergeants, lieutenants and captains.

“I am sure that the Sheriff’s Department and the Department of Police Accountability will do a thorough investigation and I hope that it is a swift one also considering the environment we are in,” Adams said. “I don’t want the community or the individual accused to have this hanging over their head any longer than is necessary.”

Supervisor Shamann Walton has introduced a ballot measure that would increase oversight of the Sheriff’s Department. If approved in November, the measure would create a seven-member panel to oversee the department and an Office of Inspector General to investigate misconduct complaints.

mbarba@sfexaminer.com