The duty which requires physicians to keep the information they receive from their patients confidential is well established in Canadian common law, health care legislation and professional codes of conduct. If a physician fails to meet this duty, he or she could face a law suit (based on the principles of negligence, contract or fiduciary law) or discipline proceedings from his or her provincial professional associations (ie, the College of Physicians).
While maintaining confidentiality is a clear legal and ethical duty, it is not absolute. There are exceptions found in both legislation and the common law. For example, Canadian child welfare laws compel physicians to disclose information about any child who may be in need of protection. Similarly, information concerning certain infectious diseases must also be given to the appropriate authorities. Because the physician-patient relationship is not "privileged," like the lawyer-client relationship, a court can compel a physician to disclose confidential information for the purposes of either a criminal or civil trial. Recent decisions by the Supreme Court of Canada have confirmed that even a psychiatrist or therapist may be compelled to disclose information in the medical records of a sexual assault victim. However, it must be shown, inter alia, that the patient's medical records are relevant to the defence of the individual who is on trial for the assault.
The most controversial exception to the duty of confidentiality, known as the "duty to warn," states that in specific circumstances physicians may have an obligation to warn a third party about a possible danger - even if the knowledge of this danger was obtained in the confines of the physician-patient relationship (eg, a psychiatrist discovering that a patient wishes to harm a third party). Emerging issues such as AIDS and the new genetic technology are straining the bounds of the "duty to warn" exception. For instance, do physicians have an obligation to warn patients' relatives that they may be at risk for a genetic disease? To date, there have been no Canadian "genetic cases"; however, the courts have held that a physician may have a duty to take steps to protect a third party - such as a patient's spouse - from exposure to the AIDS virus.