The endorsements of the Democratic candidate came from the associations representing Costa Mesa firefighters, Orange County sheriff's deputies and firefighters, and Costa Mesa police officers.
Mansoor, a Republican and former Orange County deputy sheriff, is running against Nguyen for the 68th Assembly District seat being vacated by Assemblyman Van Tran (R-Westminster). Tran is locked in a close race with U.S. Rep. Loretta Sanchez for a Congressional seat.
"What a statement that no sworn public safety employee is backing up a former deputy sheriff," said Sheriff's Association President Wayne Quint. "We see through him. This guy — he's a hypocrite."
Mansoor has criticized public employee unions for their high pay and benefits.
The 46-year-old Costa Mesa mayor, who left his post as a jailor at the county jail to focus on his campaign, is not seeking endorsements from public employee unions.
He says Nguyen, a Little Saigon businessman, will not be making the right decisions when it comes to fixing the budget deficit and addressing the high cost of pensions because he's in the unions' pockets.
Nguyen said he's endorsed by an array of organizations throughout the district and the state, including small businesses.
"I don't think Mr. Mansoor is objective himself," he said before the news conference. "Just attacking everybody that's a public employee is not objective. I'm not running to blame anyone; I'm running to solve the issues and try to find solutions and bring people together instead of blaming and scapegoating anyone who's a public employee."