Oakland police officers monitor the remnants of the Occupy Oakland encampment in front of City Hall, November 14, 2011. (CBS)

OAKLAND (CBS/AP) — A top legal adviser to Oakland’s mayor has resigned over the decision to raid the Occupy Oakland encampment Monday.

Civil rights attorney Dan Siegel is a longtime friend of Mayor Jean Quan who worked as an unpaid adviser. They both worked as student protest organizers at the University of California, Berkeley during the 1960s.

“I’m very sad about having to make this decision but I’m even sadder about the decision that Mayor Quan made to again send in the police to evict the camp at Frank Ogawa Plaza,” civil rights attorney Dan Siegel explained his decision to KCBS Monday morning.

KCBS’ Melissa Culross Reports:

Siegel has been a vocal critic of Oakland police and also had opposed the Oct. 25 Occupy raid, which turned violent.

“Prior to Oakland’s first eviction, it would have been possible for the city to work more closely with the camp to make sure their health and sanitation principals were followed and that normal enforcement and safety regulations were followed,” he reasoned in his interview with KCBS. “Once the camp was evicted I think it created such a degree of animosity and hostility that it made it very hard to put things back together again.”

Siegel said the city should have done more to work with the protesters before sending in police. He says the actions taken Monday morning could have led to more violence.

PHOTOS: Occupy Oakland Eviction

“I think (Mayor Quan) succumbed to the fact that people on the City Council were yelling to evict the camp, there were people of course in the business community, led by the Chamber of Commerce who were singing the same song. And her City Administrator put a lot of pressure on her.”

Quan confirmed Siegel’s resignation at a news conference, simply noting that the pair has been known to disagree on issues.

“I’ve known Dan since I was in college. We have our disagreements. He, um, was doing this whole project on a volunteer basis in my office. He’s moving on, I’m moving on,” she said.

“Everybody knows that it’s a very tough balancing act, people have their free speech rights in this city but also to keep the city safe, he and I will disagree and that’s it.”

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