Once a bona-fide doctor-patient relationship is established, the duty of confidentiality”attaches,” and in many states, the doctor can invoke a legal privilege, on the patient’s behalf, when asked to disclose or divulge information the doctor may have or know about the patient.
Federal Rule of Evidence (FRE) 501 provides that any permissible privilege “shall be governed by the principles of common law” as interpreted by federal courts. However, in civil actions governed by state law, the privilege of a witness is also determined by the laws of that state. Most states recognize some form of doctor-patient privilege by express law (statute), but over time, there have been many exceptions that have chipped away the use or scope of the privilege.
In recent years, many courts have held that doctors also owe duties to protect non-patients who may be harmed by patients. For example, without a patient’s permission or knowledge, doctors may warn others or the police if the patient is mentally unstable, potentially violent, or has threatened a specific person. In some states, the duty to report or warn others “trumps” the right to confidentiality or privileged communication with a doctor. Courts will decide these matters by balancing the sanctity of the confidentiality against the foreseeability of harm to a third party.