Psychotherapists is a profession that requires a licence (unless one is in training to obtain such a licence). Once it's awarded it allows one to practice the profession, provided that the ethical code established by the awarding organization is followed. Failure to comply could mean investigation by the disciplinary committee and suspension or withdrawal of the licence.
For physicians the rules are quite different and more strict, for example certain aspects are regulated by criminal law.

Art. 20:

The psychologist will give information to persons undergoing psychologist diagnoses and therapy on the methods used and results achieved, being guided by the good of these persons. The psychologist will avoid procedures which could offend the client's convictions and also the chance of erroneous interpretation of information given. In doubtful cases the psychologist will ensure that this information is correctly understood.