Why was a Texas Surgeon known for killing and incapacitating hundreds of patients allowed to practice for so long?

Resources:

Dr. Evil – Texas Monthly

Rogue Surgeon: The Tale of ‘Eric the Red’ (texasobserver.org)

Oft-sued orthopedic surgeon arrested in Colorado (chron.com)

Patients Bleed, Practice Thrives – Hartford Courant

Eric Scheffey arrested in Colorado – Off the Kuff