WATCH: Inside the big business of medical marijuana cards in Pennsylvania

HARRISBURG — A series of Spotlight PA investigations has revealed weak oversight of doctors in Pennsylvania’s medical marijuana program, prompted efforts to change state law, and led to greater transparency from the state health department.

The findings have also raised questions from experts, including fellow medical marijuana doctors, about the quality of care many patients receive when they seek a medical marijuana card.

Records obtained through legal victories bolstered Spotlight PA’s investigations. A first-of-its-kind analysis revealed how anxiety disorders came to dominate the big business of medical marijuana cards in Pennsylvania, despite limited evidence of the drug’s effectiveness and concerns about its potential to worsen anxiety symptoms.

Additional records obtained by Spotlight PA show a small number of doctors approve a disproportionately large share of medical marijuana cards in Pennsylvania, and that the Department of Health has rarely blocked doctors from joining the program based on prior discipline.

To spread the reach of this work, Spotlight PA produced broadcast-ready video segments of these investigations. The segments were created by Mitch Blacher, a veteran broadcast journalist, as part of a first-of-its-kind partnership with a group of Nexstar television stations.

Prior misconduct is rarely an obstacle for doctors in Pennsylvania’s medical marijuana program.

How anxiety dominates Pa.’s medical marijuana program.

Some Pa. doctors approve several thousand patients a year.