In Texas, nurse practitioners’ livelihoods are tied to physicians: By law, they can’t treat patients without a doctor’s permission. That means if they want to open their own practice, they must petition, and pay, a doctor to grant them “prescriptive authority” — to essentially keep an eye on their work and, in some cases, to be held liable for it. Doctors say this is as it should be. Nurse practitioners and their allies say doctors don't want the competition and charge them enough to run them out of business. “It borders on an immoral situation,” says state Rep. Wayne Christian, R-Center.