Ngunnawal resident Mitchell Ryan Laidlaw, 33, who is accused of killing disability advocate Sue Salthouse pleaded guilty to a charge of drug-driving as a repeat offender.
But Mr Laidlaw will fight a charge of culpable driving causing death; a charge which carries a potential 14-year jail sentence.
Both charges relate to a July 2020 crash that claimed the life of Ms Salthouse, who was the Senior ACT Australian of the Year at the time.