Marijuana safety labs are operating in Michigan — but what they discover is kept under wraps.

Licensors regularly check the accuracy of marijuana safety labs that make sure the product in the state is safe. Their results, however, are not shared.

Four times a year personnel are sent to a specific location by regulators to gather samples. M-Live reports that technicians look for contaminates, measure potency, and more. But the results and methodology are hidden behind a smokescreen called the Marijuana Tracking Act, which deems such information confidential. Critics say the law stifles transparency and keeps important test results from public view.

The Cannabis Regulatory Agency does issue annual and monthly statistical reports.