The La Mesa city manager hired an investigator yesterday to determine whether police officers followed regulations when they gave Mayor Art Madrid and a city employee a ride to the mayor’s home when both were apparently intoxicated.

La Mesa Police Chief Alan Lanning said he hopes the investigation will settle the questions surrounding the Feb. 20 incident.

“For those people in the community that had some concerns about the Police Department, I hope this would address those concerns and restore confidence,” he said.

The investigator is James Gardiner Associates, a consulting firm based in San Luis Obispo. A written report of the firm’s findings is expected within 30 days, according to the contract. The cost of the investigation is not to exceed $7,500.

Gardiner is a licensed private investigator who has worked for several businesses, police agencies and cities, according to the contract. It also states Gardiner has never been employed by the city and has no personal relationship or association with any city employees.

Gardiner declined to comment yesterday, but the contract lays out the scope of his firm’s investigation: “Did the two La Mesa Police Officers, and any other La Mesa Police Department officials, involved in the response to an incident regarding the Mayor and another individual on February 20, 2008, fail to comply with Department policies or procedures and any applicable law?”

That night, two La Mesa officers responded to a 911 call on Chicago Drive in La Mesa’s Eastridge neighborhood. They found city finance employee Trisha Turner, 34, in the driver’s seat of Madrid’s SUV. The engine was running, and Madrid, 73, was lying on the sidewalk nearby. Police said there was vomit around the vehicle.

Police did not conduct sobriety tests. They decided to give the two a ride to the mayor’s house about a block away but failed to call their supervisor for approval, which appears to be a violation of Police Department policy.

Allegations of special treatment prompted the city to hire Gardiner. He will be paid from a $50,000 contingency fund, City Manager Sandy Kerl said. Last week, the county District Attorney’s Office filed a misdemeanor drunken driving charge against Turner. She is scheduled to be arraigned April 10 in El Cajon Superior Court.

“I don’t have any comment,” Turner said yesterday when reached by phone.

Madrid said he supports the investigation but declined to comment further.

The city will make documents and employees, including police officers, available to Gardiner, the contract states.

Lanning said his department will cooperate, but because the department is under review, “we really shouldn’t have any input into the investigation.”