Warning: The video below contains violence that some may find disturbing.
On Tuesday, the District Attorney's Office announced they charged that officer with misdemeanor assault.
The footage released by the San Joaquin County District Attorney's Office shows Officer Matthew Mettler hit the man, who is sitting on the floor with his legs and hands cuffed and wearing a spit hood.
"I thought they took him, spoke to him, then they let him go," said Francisco Vasquez, who works at Fit Nutrition in Manteca.
Vasquez said before the officer dealt that blow last August, the man wearing a spit guard over his head for allegedly spitting at officers was passed out drunk in front of his family’s business.
"He was fully knocked out when my dad came," Vasquez said.
"I kicking his foot to move him a little bit. The guy was not responding," said Jose Guzman, who owns the business.
So Guzman called 911 then recorded the encounter between police and the intoxicated man on his phone.
"He started pushing the police officers," Guzman said.
Even though that detainee was being physically combative, the district attorney says Correctional Officer Matthew Mettler’s behavior was unacceptable and that people who abuse their power and position will be tried and punished to the full extent of the law.
Sheriff Steve Moore called Mettler's behavior inexplicable since the arrestee posed no threat. He said Mettler has been on leave ever since. In a written statement Sheriff Moore said in part:
“It is inconsistent with the professionalism of San Joaquin County Correctional Officers, and of this department. The action taken by the DA`s office is appropriate and we support their position.”
Moore also said it was a Manteca police officer who witnessed the assault inside the pre-booking area at the San Joaquin County Jail and reported it. He said he was grateful for that.
"I think it was a bit much," Vasquez said.
But his dad wonders if that deputy really did more wrong than the detainee.
"That guy was being disrespectful to the police officers. My wife, my kids, you know, this is a family business," Guzman said.
Mettler will appear in court on March 26.