While this is a reprehensible stunt by the demonrats, it's not criminal impersonation, in that she's not treating someone medically.
Since at least January 1, 1978, it has been a violation of Texas laws concerning the practice of medicine for a person:
(a) to diagnose, treat, or offer to treat any disease or disorder when that person is not licensed to practice medicine in Texas;
(b) for an unlicensed person to impersonate a licensed practitioner; and
(c) for a licensed physician to permit another unlicensed person to use his license or certificate to actually practice medicine. I.G. Ex. 66, 7/ 11 at 141-143; I.G. Ex. 99.
As such, it is a separate subsection of the criminal statute to claim you are a “medical doctor”, not just a “doctor” which could legally be a PhD. In her case, she claimed to be a Pediatrician. There is *no* non-licensed as a Medical Doctor form of being a Pediatrician.
I’d like to add that Texas is probably the *worst* State in the US to pretend to be a medical doctor, because they get a lot of Mexicans who pretend to be doctors and dentists, and this has led to some very nasty incidents.