The husband of Alameda Mayor Trish Spencer has filed a claim against the city and its Police Department, alleging that officers stopped him without probable cause and arrested him on false allegations that he was driving drunk on St. Patrick’s Day.

Joel Spencer’s claim, filed this week in Alameda County Superior Court, states he is seeking compensation for “injuries to the body, defamation of character, (and) costs and fees to defend himself in (a) criminal proceeding.” The city has 45 days to settle or deny the claim, at which point Spencer can file a lawsuit.

Court records show that Spencer was arrested on March 17 on misdemeanor charges of driving under the influence. He pleaded not guilty on April 18, and the criminal case against him is pending.

“We are a little puzzled,” said Alameda City Attorney Janet Kern, adding that the mayor and the City Council are both aware of the complaint, and that the city intends to investigate it “as we would anything else.” The mayor will not take part in that investigation, Kern said.

“We’re also looking to see what the criminal case is going to do,” Kern said. “Frankly, I don’t know why they decided to file this now.”

The mayor did not return calls or respond to an email on Friday, and her husband could not be reached for comment. His attorney, Andrew Dosa, declined to comment.

An Alameda Police Department spokesman was also unavailable for comment Friday.

Kern said that she and other city officials are confident that their police force “does a very good job.”

“We have no reason to believe there was improper conduct on the part of our police officers, particularly since the district attorney has decided to prosecute,” she said.

Rachel Swan is a San Francisco Chronicle staff writer. Email: rswan@sfchronicle.com Twitter: @rachelswan