According to prosecutors, 37-year-old Michel Martin's son was driving a semi truck that hit and killed two women.
Prosecutors filed new felony charges, upping the potential penalties in the case for the father.
State troopers said Martin's 16-year old son was driving the family's semi truck westbound on Interstate 70 on July 14 near Limon.
That's when, they say, he fatally hit 48-year-old Shun Jones of Carrolton, Tex. and 38-year-old Amanda Omo-Iyamu of Balch Springs, Tex., who were changing a tire on the side of the road.
State troopers say he pulled over about a half mile away from the crash scene and someone else drove the 16-year-old away from the scene.
Prosecutors also say Martin tried to cover-up the fact his son was driving to a state trooper investigating the accident.
It's still unclear whether the 16-year-old was licensed to drive the semi.
Martin, his wife, and their son left the courthouse Friday without making any statements.
Both Martin and his son will appear at the Lincoln County Courthouse September 21 for their preliminary hearings.
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