HARRISBURG -- A veteran of the Hummelstown police department who is facing charges in the shooting of an unarmed man appeared before a Dauphin County judge this morning and pleaded not guilty to the charges against her.

Lisa Mearkle, who spent 14 years as an officer with the department, was charged with third-degree murder, voluntary manslaughter and involuntary manslaughter after the fatal shooting of 59-year-old David Kassick, according to court records.

She is accused of using excessive force in Kassick's death. State police allege she shot the unarmed man without justification when she fired two fatal rounds into his back while he was lying on the ground.

The incident followed an attempted traffic stop in South Hanover Township in February.

Mearkle's attorney, Brian Perry, has argued the shooting was justified because the officer believed Kassick had been reaching into his jacket for a weapon.

Perry entered the not guilty plea on behalf of his 36-year-old client before Judge Deborah E. Curcillo at 8 a.m. on Thursday in what Chief Deputy District Attorney Johnny Baer estimated to be a three-minute proceeding.

Mearkle's next scheduled court appearance is in November.