Military prosecutors say a Navy doctor accused of secretly videotaping Naval Academy midshipmen engaged in sexual acts committed a "flagrant violation of trust."

A court-martial began Monday for Commander Kevin J. Ronan, who allegedly used a video camera secreted in an air purifier to tape midshipmen he hosted at his house last year. On Tuesday, Dr. Ronan's accuser and alleged victim took the stand. He claimed he found a disk of gay pornography near Ronan's computer which prompted him to start snooping around. The victim said he found explicit videos of himself and his friends then searched more and found a secret spy camera set up in a room used by visiting mids and a linked recording device in Ronan's bedroom.

On cross examination, Ronan's attorney attacked the 22-year-old's credibility. The young man admitted he was kicked out of the academy for poor grades and then forged a phony college acceptance letter to avoid paying for his schooling with cash or active duty time as an enlisted man. He allegedly lied to investigators about how many DVD's he had taken from Ronan's home. The defense is the accuser actually staged the whole thing in an effort to blackmail Ronan for money.

Ronan's attorney, William Ferris, says his client did not make the videotapes and that he bought the air purifier with the camera only to check on whether his midshipman were having parties while he was away.

The case is expected to last two weeks.