PORTLAND – A Portland police officer found innocent last year of assaulting a criminal suspect is being sued by the law firm that represented him in the case.

The firm Beagle and Ridge has filed a lawsuit in Cumberland County Superior Court claiming Brian Regan owes it $14,000 in legal fees and has not responded to requests for payment.

Regan signed a contract in October 2002 agreeing to pay the firm up to $15,000 to defend him, according to court documents. But he had paid only $1,000 as of June 13, 2003, and has paid nothing since.

The bill is the result of assault charges against Regan and his partner, Patrick DeCourcey, accusing them of using excessive force on a criminal suspect, Michael Esposito, during an arrest in 2002. At the time, Regan was a detective assigned to the Maine Drug Enforcement Agency.

When the case went to trial last year, Regan was represented by Martin Ridge. After less than two hours of deliberations, the jury returned a unanimous verdict in favor of both officers.

Reagan did not return a phone message left at the Portland Police Department, where he works as a patrolman. Barry Woods, the lawyer representing Beagle and Ridge, would not comment about the case.

Regan and DeCourcey were also named as defendants in a civil rights case, which was settled in April with the city and state agreeing to pay a total of $85,000 to Esposito.

The lawyer who helped Regan get his job back said Portland should pay the officer’s legal bills, especially since he was acquitted of the criminal charges.

John Chapman said because of the nature of their work, police officers are vulnerable to criminal charges, and their legal defense should be considered a cost of doing business.

“Every arrest is a kidnapping, every use of force is assault if you don’t have justification,” Chapman said. “If you are not wrong at the end of the day, the employer should pay.”