Most jails in the US use one of five companies to provide medical "care" to prisoners, and those companies do a measurably bad job.

These companies are successful because they charge less, and they reduce costs by cutting corners — for instance, by being slow to approve permitting a prisoner to be seen by a professional. This is the standard problem with privatizing all or part of a public activity.

Therefore, I suggest that contracting a public function to a private activity should be forbidden by law if the activity involves doing things specifically for, or to, individual members of the public.