HARRISBURG, Pa. (AP) — The Pennsylvania Supreme Court on Thursday struck down a county’s policy that forbade people on probation and other forms of supervision from using cannabis if they are registered in Pennsylvania’s medical marijuana program.

The justices said that probationers holding a valid medical marijuana card are immune from punishment under the state’s medical marijuana law.

Lebanon County’s court system had sought to prohibit medical marijuana use by people on probation and parole. The county court said that since marijuana use remains illegal under federal law, judges and the probation department “should not knowingly allow violations of law to occur.”

The county’s policy was challenged by three medical marijuana patients.

Pennsylvania’s medical marijuana law permits legal use of the drug for a range of medical conditions, following certification from a doctor.