The vehicle was found in the lake on July 31 and Connie Crowell, 54, and her son, John Crowell, 22, were pronounced dead at the scene.
Connie and John, from Monroe, were in the car and seatbelted in when crews found them, according to police and they succumbed to drowning.
Police said a boater tried several times to rescue the mother and son, but Connie Crowell refused to acknowledge pr accept the boater's help.
The deaths have been rule a homicide/suicide.
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