An unlicensed driver accused of causing a fatal head-on collision while driving home from a methadone clinic has been charged with homicide by vehicle while driving under the influence of a controlled substance.

A drug recognition specialist has asserted that 25-year-old Justin Enslen of 106 Rosewood Lane was impaired by a “narcotic analgesic” at the time of the Monday morning crash.

Enslen, driving a Dodge Ram pickup truck on Route 68, reportedly swerved into the lane of opposing traffic in front of the Connoquenessing Elementary School. The truck crashed head on with a Nissan Frontier driven by Mark Bishop, 52, of Oakland Township.

Bishop died in the crash. His sister, Holly Merkner, 41, of Lyndora, a passenger in the Frontier, was taken by ambulance to Butler Memorial Hospital.

Enslen was taken to Allegheny General Hospital in Pittsburgh where he reportedly told an investigator he’d been driving home from a regular visit to a methadone clinic in Cranberry Township. Methadone is a prescription narcotic mostly known as a treatment for heroin addiction.

Court records say a state trooper trained to recognize people who are under the influence of drugs evaluated Enslen at the hospital, and determined that he was impaired.

In addition to the homicide charge, Enslen was charged Tuesday with accidents involving death while not properly licensed, two counts of driving under the influence of a controlled substance, driving while operating privilege is suspended or revoked, driving on the wrong side of the road, careless driving, reckless driving and a seat belt violation.

Court records indicate that Enslen’s extensive criminal record includes a 2005 driving under the influence conviction that caused his license to be invalid.

A preliminary hearing will be scheduled in the Evans City office of District Judge Wayne Seibel after Enslen is released from the hospital.

Assistant District Attorney Mark Lope, who is prosecuting the case, declined to comment.