Doctor-patient confidentiality lies at the heart of the medical ethical code in Germany, as it does all over the world.
It has also been at the core of a debate following the 2015 Germanwings crash, which was caused deliberately by a co-pilot found to have been struggling with mental health troubles for years.
"Physicians are obliged to maintain confidentiality regarding everything confided in them, or becoming known to them, in their capacity as a physician, including after the death of the patient," Article 9 of the German Medical Association's professional code states clearly.
This applies also to providing information to family members.
However, doctors may provide information if they are released from their obligation to maintain confidentiality, "or insofar as disclosure is necessary in order to safeguard a higher-ranking legally protected interest," the code states.
If more than one doctor is treating the same patient, they are also permitted to exchange information "insofar as the patient's informed consent has been given or can be assumed."
Even if doctors are not released from their obligation to maintain confidentiality, the confidentiality rules may be overridden under the German criminal code if an "exceptionally serious crime" could thereby be prevented or if there is danger to life.
The medical association provides the example of an HIV patient, whose partner may be informed of the condition if the patient resists doing so.
A doctor may also convey information to the medical insurance company of the patient, for example if the patient is judged to be unfit for work.
Any doctor who breaches the confidentiality code is liable to a jail term of a year or a fine in terms of the German criminal code. This provision applies as well to psychologists and others working as healers.