ALFRED, Maine (AP) -- A computer expert says a Maine man charged with promoting prostitution deleted his email a day after police raided a fitness instructor's dance studio, office and home in February 2012.

Frederick Williams from the Saco Police Department told jurors Monday that he found spreadsheets, tax documents and snapshots from video chats on defendant Mark Strong's computer. But jurors weren't told he'd taken snapshots of his lover, fitness instructor Alexis Wright, engaging in prostitution in Kennebunk.

The defense says the evidence is prejudicial and that possessing pornography isn't a crime; the judge didn't immediately rule on whether photos can be shown to jurors.

Strong, a Thomaston insurance agent, is on trial for 13 counts related to promotion of prostitution. Wright will be tried later. Both have pleaded not guilty.