*528 OPINION OF THE COURT
Hospitals may assert a physician-patient privilege under CPLR 4504 (a) to maintain the confidentiality of patient medical records. The case before us involves the extent to which grand juries may, compatibly with CPLR 4504 (a), acquire medical records for the purpose of identifying criminal assailants.
On May 25, 1998, an unidentified assailant stabbed a man to death in Manhattan. Police could determine only that the assailant was a Caucasian male in his 30s or early 40s and that he may have been bleeding when he fled the scene. Over 2V2 years later, still unable to identify him, the District Attorney of New York County conjectured that the assailant may have sought medical treatment at a local hospital shortly after the homicide. In early 2001, the District Attorney served grand jury subpoenas duces tecum on 23 hospitals, including four facilities operated by the New York City Health and Hospitals Corporation (HHC). Those subpoenas sought:
“[a]ny and all records pertaining to any male Caucasian patient between the ages of 30 to 45 years, who was treated or who sought treatment on May 25th, 1998 through May 26th, 1998 for a laceration, puncture wound or slash, or other injury caused by or possibly caused by a cutting instrument and/or sharp object, said injury being plainly observable to a lay person without expert or professional knowledge; said records including but not limited to said patient’s name, date of birth, address, telephone number, social security number and other identifying information, except any and all information acquired by a physician, registered nurse or licensed practical nurse in attending said patient in a professional capacity and which was necessary to enable said doctor and/or nurse to act in that capacity.”
Citing CPLR 4504 (a),
1
HHC invoked the physician-patient privilege and refused to turn over emergency room triage logs
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potentially responsive to these subpoenas, claiming that compliance would necessarily breach patient confidentiality in violation of the statute. After the District Attorney moved to hold HHC in contempt, HHC cross-moved for an order quashing the subpoenas. Supreme Court denied both motions but ordered HHC to submit the records for in camera inspection. The Appellate Division unanimously reversed and granted the motion to quash, holding that compliance with the subpoenas would violate the physician-patient privilege because “the assessment of the nature and cause of the injuries triggering production of the relevant documents involves an inherently medical evaluation” (
Our analysis begins with the history and purpose of the physician-patient privilege. Common law did not recognize any confidentiality in communications between patients and medical professionals. New York was the first state to enact a physician-patient privilege statute
(see
2 Rev Stat of NY, part III, ch VII, tit III, § 73 [1st ed 1829];
see also Dillenbeck v Hess,
Though in derogation of the common law, the physician-patient privilege is to be given a “broad and liberal construction to carry out its policy”
(Matter of Grand Jury Investigation of Onondaga County,
On this appeal, the District Attorney contends that enforcement of the subpoenas would not offend these policies or violate CPLR 4504 (a). The prosecutor argues that the subpoenas do not seek information acquired by means of medical diagnosis, treatment or expertise, and should be enforced because they purport to seek records only of injuries “plainly observable to a lay person without expert or professional knowledge.” We disagree.
The physician-patient privilege generally does not extend to information obtained outside the realms of medical diagnosis and treatment. Indeed, because the policies underlying the physician-patient privilege implicate confidential patient relationships with medical professionals
as
medical professionals, we have generally limited the privilege to information acquired by the medical professional “through the application of professional skill or knowledge”
(Dillenbeck,
We conclude, however, that
Onondaga County
controls this appeal and directs that the challenged subpoenas be quashed. In
Onondaga County,
as in the instant case, the victim was stabbed to death under circumstances that led investigators to conclude that the assailant may have left the scene bleeding. Endeavoring to identify the assailant, the District Attorney of Onondaga County issued a grand jury subpoena on a hospital, seeking, “all medical records pertaining to treatment of any person with stab wounds or other wounds caused by a knife”
(Onondaga County,
We perceive no difference of any actual substance between the subpoena quashed in Onondaga County and the ones challenged here. The records potentially responsive to the HHC subpoenas are precisely the same as those sought in Onondaga County. Though the District Attorney crafted the instant subpoenas with Onondaga County in mind by broadening their scope (to include most bleeding wounds rather than only knife wounds) and narrowing their reach (to include only wounds “plainly observable to a lay person”), the subpoenas still run afoul of Onondaga County.
Here, much as in
Onondaga County,
the challenged subpoenas define the class of records sought by the “cause or potential cause” of injury. Thus, the subpoenas inevitably call for a medical determination as to
causation
“through the application of professional skill or knowledge”
(Dillenbeck,
By merely reviewing hospital records after patients obtain emergency medical treatment, hospitals cannot reasonably determine whether particular injuries and their causes would have been obvious to a layperson. Medical records are *532 not organized on the basis of what laypersons — as opposed to medical professionals — might discern. Even if a particular medical record does state the cause of injury, the record may not indicate reliably how the hospital ascertained the cause. Medical professionals may have learned the cause from the patient, or discovered it based on their medical expertise. Hospitals should not face contempt proceedings merely because they cannot distinguish the indistinguishable.
This result is further justified by the policy objectives of the physician-patient privilege and the broad construction of CPLR 4504 (a) required to achieve them. Patients should not fear that merely by obtaining emergency medical care they may lose the confidentiality of their medical records and their physicians’ medical determinations. A contrary result would discourage critical emergency care, intrude on patients’ confidential medical relationships and undermine patients’ reasonable expectations of privacy.
Finally, we note that none of the Legislature’s many statutory exceptions to the physician-patient privilege apply here. For example, notwithstanding CPLR 4504 (a), Public Health Law § 2101 (1) obliges physicians to disclose immediately any case of communicable disease
(see Thomas v Morris,
Inasmuch as the Legislature enacted an exception to CPLR 4504 (a) directing the reporting of potentially life-threatening stab wounds
(see
Penal Law § 265.25), we reaffirm our conclusion that the Legislature intended CPLR 4504 (a) to protect
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against disclosure those medical records of patients whose stab wounds are less severe
(see Onondaga County,
Accordingly, the order of the Appellate Division should be affirmed, without costs.
Chief Judge Kaye and Judges Smith, Levine, Ciparick, Wesley and Graffeo concur.
Order affirmed, without costs.
Notes
. CPLR 4504 (a) provides, in pertinent part: “Unless the patient waives the privilege, a person authorized to practice medicine, registered professional nursing [or] licensed practical nursing * * * shall not be allowed to disclose any information which [s]he acquired in attending a patient in a professional capacity, and which was necessary to enable him [or her] to act *529 in that capacity. The relationship of a physician and patient shall exist between a medical corporation * * * and the patients to whom [it] * * * render[s] professional medical services.”
. We recognize that courts may properly decline to enforce the physician-patient privilege where its invocation does not serve its policy objectives. Thus, for example, “a person or entity subject to proceedings for having committed crimes against an individual should not be permitted to assert the victim’s physician-patient privilege as a bar to production of relevant medical records or testimony”
(Matter of Grand Jury Proceedings [Doe],