The father of a man killed by Sonoma County deputies said Friday his bad son’s behavior didn’t warrant his death in a hail of police bullets.

Ernie Sullivan said he was disappointed by this week’s ruling from the District Attorney’s Office that the five deputies were justified in last year’s shooting of Nicodemus Sullivan, 24, of Santa Rosa.

The father said even though his son violated a restraining order by going to his childhood home and refusing to get out of his car, the use of deadly force was unwarranted.

“I think it was ill-advised behavior for him, absolutely,” said Sullivan, a Caltrans heavy equipment operator from Richmond. “But to be shot to death in the street over it doesn’t add up.”

Nic Sullivan was killed Oct. 29, 2010 outside the house on Hargrave Avenue where his mother and stepfather, Reyes Lopez, lived.

Police said the convicted felon had been threatening the stepfather and had been recently found in possession of a loaded shotgun.

Deputies were called when Sullivan showed up at the house, in violation of a court order. A standoff ensued as he was backing out of the driveway.

Deputies tried for up to 30 minutes to get him out of the car. When talk failed, they broke a window, used a stun gun and brought out a police dog.

That’s when police said Sullivan stomped his foot on the accelerator of his Nissan Altima and attempted to flee, ramming at least two patrol cars. Five deputies opened fire, shooting him 11 times. He died from two blasts to the chest.

Santa Rosa police investigated the shooting and turned over findings to prosecutors. The District Attorney’s Office concluded there was no criminal liability for any of the deputies.

But the father disagreed. He said deputies had “other tools” they could have used and explained his son’s reluctance to get out of the car as a possible fear of getting mistreated by officers.

His son had served a year in prison for car theft, he said.

The father said the gun possession charge was blown out of proportion. His son was moving his belongings, including the shotgun, and had temporarily parked at his mother’s house, when he was rousted by deputies.

Tension between his son and Lopez developed when Lopez told him to leave his mother’s property, Sullivan said.

“He said, ‘Get off my property,’” Ernie Sullivan said of Lopez. “Nic grew up there and felt it was his family’s property.”

Sullivan said it was not clear if investigators knew the history. He said they would not share their reports.

Also, he’s unconvinced his son actually rammed any patrol cars. And he heard shots were fired at his son after he was slumped over in the driver’s seat.

Bottom line: he said the deputies should have been charged. If nothing else, he said the District Attorney’s Office should have recommended training to prevent future killing.

“The cops made a big error here,” Sullivan said. “It’s a big mistake. I’m very disappointed in the ruling. It just perpetuates the problem.”