When Jennifer Casey Norred attempted suicide at Leon county jail in Tallahassee, Florida, medical staff didn’t take her to the emergency room or provide mental health support. Instead, they strapped her to a chair for 24 hours, according to jail records. The jail’s own policy requires that restraint chairs only be used as a last resort, and not for more than two hours.

It was the kind of policy violation that has become more common nationwide since two private equity-backed prison health companies, Corizon and Wellpath, have come to dominate the industry, experts say.

An investigation by the Guardian published on Monday revealed how Wellpath and Corizon (now renamed YesCare) have remained leaders in the business of providing healthcare to incarcerated people even though multiple government bodies, including the Department of Justice, have documented cases where these companies’ failure to provide adequate care violated prisoners’ constitutional rights and in some cases was even linked to preventable deaths.