Cobb County State Court Judge Kathryn Tanksley said no Saturday to General Motors’ motion to dismiss a lawsuit accusing the company of covering up a deadly ignition switch defect.

The lawsuit before the court in the unusual Saturday session — set to accommodate scheduling conflicts of GM lawyers — was filed by Kenneth and Mary Elizabeth Melton over the 2010 death of their daughter, Brooke, a 29-year-old nurse. The Meltons allege that their daughter died because of a defective ignition switch in her 2005 Cobalt that suddenly shut off the car’s power in traffic, leading to a crash and a rollover. The investigation leading up to the lawsuit discovered the defect now at issue in hundreds of other product liability cases and in GM recalls that now cover approximately 19 million cars.