An autopsy has determined the wife of a state lawmaker drowned in the Payette River.  The body of 49-year-old Mary Jo Roberts was pulled from the river Saturday. She is the wife of Republican House Majority Caucus Chair Ken Roberts of Donnelly. Valley County Sheriff's Lt. Dan Smith says an autopsy completed Tuesday determined that the cause of death was drowning. Smith says the manner in which the woman died is still under investigation. She was reported missing last Friday after she failed to show up for work and her car was located near a bridge in McCall. Her body was found the next day in a log jam about six miles downstream from the central Idaho city.