Gunnery Sgt. Eric Froboese pleaded guilty Thursday to disobeying a lawful order, dereliction of duty and conspiracy. Other charges were dismissed as part of an agreement with prosecutors.
The hearing at Camp Pendleton did not reveal the contents of the files, which were deemed classified by CIA and shared with the sheriff's deputy between 2003 and 2004.
The maximum sentence is 10 years in the brig, pay forfeiture, a reduction in rank to private and dishonorable discharge. A sentencing date has not been set.
Two other Marines are charged in the same case. One has pleaded guilty.