DANBURY — More than two years after former police officer Christopher Belair was caught on video yelling profanities at an undocumented immigrant during a traffic stop, a jury on Thursday found him not guilty of the criminal charges that resulted. Belair, 35, of Waterbury, had been charged with third-degree assault and second-degree threatening following a monthslong State Police investigation, which began when Rene Chalco told internal affairs officers Belair had not only verbally abused him but punched him in the mouth in the March 2013 incident. “The video simply does not show any assault,” Defense Attorney Eugene Zingaro told the jury during his closing arguments Wednesday. Belair, who had been with the police department for five years, was fired by Mayor Mark Boughton in June 2013 after a disciplinary hearing that led to the suspensions of the other officers. “Pretty much my entire career has been spent trying to help people,” said Belair, who has been a volunteer firefighter, a police dispatcher and an emergency service technician. Chalco did not pursue legal action, but the recording Howley made circulated through the police department until the command staff heard about it and started an internal affairs investigation, court documents show. Boughton, who has taken a hard stance on illegal immigration, said there was “nothing political” about his decision to fire Belair. “His behavior in March 2013 is certainly not reflective of his training, certainly not reflective of any standard operating procedure by any law enforcement agency in the state of Connecticut, and not reflective of the core values of the Danbury Police Department, which includes respect,” Baker said.