Many big city police officers carry assault weapons in their vehicles, but not in San Francisco.

Despite a crime wave that has left 55 people, including a police officer, dead at the hands of criminals with high-powered weapons, some fear more violence if cops are comparably armed.

"It terrifies the citizens of many neighborhoods in San Francisco, as it should, the idea that they would be living in a place where there might be some regularity of armed battles with assault weapons," said Peter Keene (search), San Francisco police commissioner.

In a city that’s district attorney refuses to seek the death penalty for a cop-killer, the police commissioner's resistance comes at no surprise to the police union.

"They can do whatever they want, and that's fine until it starts to endanger the safety of my officers and then it's a different story," said Gary Delagnes, president of the San Francisco Police Officers' Association (search).

Commissioner's politics, police say, aren't much protection against heavily armed thugs. If cops don't get the firepower they need to protect their city, they promise to take their fight to the state legislature and Governor Arnold Schwarzenegger (search).

Click on the video box at the top of this story to watch a report by FOX News' Claudia Cowan.