Chao has been sued 18 times, including four times by Chargers players, for medical malpractice, negligence, or fraud. He currently serves as the head physician for the San Diego Chargers and has not been popular with the NFL Players Association. NFL Players Association executive director DeMaurice Smith stated the following about Chao..
"The concerns we have about Dr. Chao remain. The fact is that despite having previous malpractice liability (awards) against him, neither the Chargers nor the NFL initiated an inquiry or provided any oversight of the doctor the team selected to provide care for our players."