Stopping services to a patient without following the proper guidelines is considered abandonment. Next to suicides, it is the largest cause of malpractice lawsuits against psychiatrists.
Stopping services is going to depend on the state. Pretty much all states require the provider to provide referrals to other providers but the specifics vary by state. Some states only require referral to one doctor, some require 3. If patient do not follow guidelines set forth that they agreed to follow, the provider can terminate the patient. E.g. a patient that is a no-show several times, but again you need to be wary of the specifics the state demands. Some states may require a specific number of no shows.
Just an example, here are the state laws of Ohio where I practice. Many states will have their laws printed online for you to reference.
http://codes.ohio.gov/oac/4731-27
If a patient is pissing staff off, that is not enough grounds to terminate treatment. Several psychiatric patients fit profiles where they will be very difficult. Further, some personality disorders such as borderline PD need treatment and people with this profile often upset people.
I've seen cases where doctors stopped services to borderline patients without referrals because they were difficult. IMHO, those cases are on thin ice for losing lawsuits but I never saw a malpractice case yet from it. I've also talked about this before on this forum. Many psychiatrists treat borderline patients with psychotropics even though that is not the first line treatment and meds have only minor benefits for borderlines. A psychiatrist abandoning a borderline is playing with fire. You got...
1) a patient with a profile where they are more likely to sue
2) a patient who may have been improperly treated (not given the first line treatment and not given DBT which is considered the appropriate treatment)
3) abandonment that fits the legal definition of the term.
IMHO this is even more reason why psychiatrists should not treat borderline patients with meds and either provide DBT or refer the patient to someone who can do DBT. Unfortunately the trend I see is the psychiatrist diagnoses them as bipolar disordered, gives them a mood stabilizer and the patient gains 100 lbs and is no better off.