The public has a right to every man’s evidence, unless that evidence is protected by a constitutional, common-law, or statutory privilege. How should this doctrine apply where a litigant seeks discovery of the identity of a nonparty patient who may have been a witness to negligence or malpractice? At what point is the right to evidence trumped by a patient’s right to privacy? When addressing such questions, courts distinguish the situation where disclosure of a nonparty patient’s identity would reveal nothing more than the fact that the person was a patient from the situation where such disclosure would reveal the nature of the person’s ailment or treatment.

Thus, an Arizona court allowed discovery of the identity of a hospitalized patient who may have witnessed events relevant to a malpractice claim brought on behalf of his hospital roommate. The court allowed such discovery on the basis that revealing that a person was a patient in a particular hospital room on a particular day would not reveal anything of importance about the nature of his ailments or treatment.1 Along similar lines, a New York court allowed discovery of the identities of nonparty patients in an emergency room because, due to wide range of services and medical conditions treated in emergency room, disclosure of their identities would not violate their right to keep their personal health information confidential.2

In contrast, a New York court did not allow discovery of the identities of patients in a cardiac rehabilitation center who may have witnessed an injury that was the subject of a lawsuit.3 This court did not allow such discovery because it necessarily would have revealed the nature of their ailment. It would have revealed “that they were undergoing treatment for cardiac-related conditions.” One might expect a court following this reasoning to bar discovery of the identity of a nonparty patient if it required revealing that they were receiving treatment in a particular part of a hospital (such as cancer radiation) or were hospitalized in a facility that provided a particular kind of care (such as a cancer or orthopedic specialty hospital).