ALFRED, Maine (AP) — The Kennebunk Police Department is feeling vindicated after one of two accused co-conspirators was convicted in a prostitution case that led some to criticize the department and question its priorities.

The defense attacked the motives of the lead investigator, the handling of evidence and the conduct of officers during the trial of Mark Strong Sr., who was convicted of 13 counts of promoting prostitution. The date for his sentencing was changed Thursday to March 21 in York County Superior Court.

"What are you going to do when you have no other defense? Obviously the jury saw through that and it didn't work for out," Police Chief Robert MacKenzie told reporters after the verdicts.

Defense lawyer Daniel Lilley criticized the chief investigator, questioning why a "rookie" was assigned to the case instead of a detective. He also accused her of targeting his client because Strong, a licensed private investigator, was looking into unprofessional conduct, including her affair with a former superior. Lilley also sent a letter to town selectmen asking her to be taken off the case.

MacKenzie praised the investigator, Officer Audra Presby, for maintaining her focus, saying she "did a great job despite those personal attacks."

The case began with anonymous emails to the department suggesting that Zumba instructor Alexis Wright was using her studio as a front for prostitution.

Police served search warrants at Wright's home, office and studio on Feb. 14, 2012, and seized computers, hard drives and other devices containing videos of her clients. The investigation led police to Strong, whose home and office in Thomaston were raided in July.

One of the hard drives from Strong's office ended up in the trunk of Presby's cruiser instead of state police custody.

The defense suggested the hard drive contained findings from Strong's investigation into alleged unprofessional conduct by Kennebunk officers before being erased. Prosecutors said it was a simple mistake.

Lilley publicly called for Presby to step down because of a protection-from-abuse order against her for sexual contact with a minor. It was determined to be unfounded.

As for the affair, Presby's former superior, Lt. Nick Higgins, resigned from the department. They remain a couple, and Higgins was seated with Presby when the guilty verdicts were announced.

Presby said she's happy to be vindicated.

"Law enforcement doesn't come out here every day to play games. This is not a game. I took my job seriously and I'm proud of myself and my department," she said.

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