Duty to warn refers to the responsibility of a counselor or therapist to inform third parties or authorities if a client poses a threat to himself or herself or to another identifiable individual. Legal duty to warn was established in the case of Tarasoff v. Regents of the University of California (1976), where a therapist failed to inform a young woman and her parents of specific death threats made by a client. The young woman was subsequently killed and her family sued the therapy provider.
The case of Jablonski by Pahls v. United States further extended the responsibilities of duty to warn by including the review of previous records that might include a history of violent behavior. The ruling originated from a case in which a doctor conducted a risk assessment of a client, Mr. Jablonski, but did not review Jablonski's past history of violence. As a result, the client's girlfriend, Ms. Kimball, was not warned about Jablonski's history of violent behavior. When the Jablonski was released, he then killed Kimball.
Duty to warn gives counselors and therapists the right to breach confidentiality if a client poses a risk to another person. It also protects clinicians from prosecution from breach of confidentiality if they have reasonable suspicion that the client might be a danger to himself or others.