Sexual assault charges dropped against San Francisco commissioner

William Monroe Palmer, a board member on the San Francisco Sheriff's Department's Oversight Board has been arrested on sexual assault and other charges.  (San Francisco Sheriff's Department Oversight Board)

Sexual assault charges have been dropped against a member of the San Francisco Sheriff's oversight board.

William Palmer, 53, was charged in an alleged incident that happened in his home last August. He pleaded not guilty and was jailed in November.

Assistant District Attorney Katherine Wells said new evidence has surfaced from out of state, that could impact the alleged victim's credibility.

"This decision does not negate the physical injuries to the victim, Mr. Palmer’s DNA on the victim’s neck, video of the victim running away from Mr. Palmer asking for help, her 911 call reporting the same, and Mr. Palmer’s changing statements," said Wells.

The assistant DA's office said they reserve the right to re-file the case.

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