Insurer Must Defend on All Counts if One Is Covered: O’Connor v. MAG Mutual (SJC-13821, August 7, 2026)

When the Board of Registration in Medicine moved to suspend Dr. William O’Connor’s license based on a patient’s complaint, his insurer refused to pay defense costs. The board complaint described a grim pattern: stalking, trespass, stolen mail, harassment. It also alleged that O’Connor had prescribed an addictive medication to the patient for six years, continuing to write prescriptions after her primary care physician stopped doing so because of addiction concerns.

The Supreme Judicial Court ruled that the insurer must cover O’Connor’s defense costs for the entire proceeding. The court held that while criminal allegations do not constitute professional services, the prescription allegation does. Because at least one count fell within the policy’s regulatory defense provision, the insurer must defend all counts, including the uncovered ones.

The Policy

O’Connor purchased his policy from MAG Mutual for the year beginning September 1, 2019. The policy included a limited regulatory defense provision requiring the insurer to pay defense costs for administrative proceedings that arise out of a patient complaint about the insured’s professional activities. Professional activity was defined as providing medical professional services to a patient. The policy did not define professional services.

The Complaint and Denial

In December 2019, the patient’s husband filed a complaint with the board. He recounted that an abuse prevention order had issued against O’Connor for stalking and that the physician had violated it by trespassing and attempting to break into the patient’s home. An arrest warrant had issued. The husband also stated that O’Connor had been in a romantic relationship with the patient from 2008 to 2016 and had prescribed an addictive medication to her for about six years during this period. The husband alleged that O’Connor prescribed the drug when the patient’s primary care physician refused to continue prescriptions due to addiction concerns. The patient believed O’Connor used the drug’s addictive qualities as leverage to keep her in the relationship.

The board investigation confirmed the allegations. In February 2020, the board’s complaint counsel moved for summary suspension of O’Connor’s license, arguing he posed a serious threat to the public.

O’Connor notified MAG Mutual and requested regulatory defense coverage. The insurer refused. It reasoned that the alleged conduct predated the coverage period, that the complaint came from the husband rather than the patient, and that the allegations of stalking, trespass, and theft did not relate to professional services. The insurer suggested that even the prescribing allegation might involve violations of laws unrelated to the standard of care.

What the Superior Court Held

O’Connor sued for declaratory relief, breach of contract, and violations of chapter 93A. The case proceeded on agreed facts. The trial judge ruled for the insurer, finding that the board proceedings did not arise from professional activities but from criminal conduct. The judge stated that prescribing medication for the purpose of coercing the patient to continue the relationship could not be construed as providing professional services.

The SJC’s Analysis

Justice Wendlandt wrote for the court. The analysis turned on whether the operative complaint was reasonably susceptible to an interpretation stating a claim covered by the policy. The insurer’s duty to defend arises before the merits are resolved. Any uncertainty is resolved in favor of the insured.

The court applied the test from Roe v. Federal Insurance Co. A professional service arises out of work involving specialized knowledge where the labor is predominantly mental or intellectual. The inquiry focuses on the act itself, not the actor’s credentials. Membership in the profession must require special learning, the professional must apply that learning when rendering patient care, and there must be a causal relationship between the alleged harm and the professional act.

The criminal allegations failed this test. Stalking, leaving harassing messages, stealing mail, surveilling property, trespassing, and attempting to break into a house require no medical training. There is no causal relationship between those acts and any professional service. The only connection to the medical profession is that a physician allegedly committed them.

Prescribing as Professional Service

The prescription allegation required a different result. Prescribing medication is an act requiring membership in a licensed profession. State and federal law govern who may prescribe and under what circumstances. The Controlled Substances Act mandates that prescriptions be issued for a legitimate medical purpose by a practitioner acting in the usual course of professional practice.

Prescribing medication, especially controlled substances, requires specialized knowledge and the application of special learning. The operative complaint could be read to allege that O’Connor was rendering care to the patient, who had been receiving the medication from her primary care physician. A fair inference is that the patient was potentially harmed by O’Connor’s continued issuance of prescriptions when another physician judged that the drug’s addictive qualities counseled against further prescriptions. This establishes the requisite causal relationship.

The court distinguished Roe, where a dentist sexually assaulted a patient after administering novocaine. That case involved indemnification, not the duty to defend, and there was no finding that the novocaine itself harmed the patient. Here, the complaint gives rise to an inference that the patient suffered injury from the continued prescriptions, separate from the prolonging of an unwanted relationship.

In for One, In for All

Having concluded that the prescription allegation constitutes a professional service, the court applied the rule that when an insurer is obligated to defend on one count, it must defend on all counts, including those not covered. The rationale is practical: dividing representation between covered and uncovered claims is unworkable.

The court vacated the judgment for the insurer and remanded for further proceedings.

Why It Matters

The decision clarifies the scope of regulatory defense provisions in medical liability policies. Insurers cannot avoid their duties by pointing to uncovered allegations when the complaint also includes covered ones. The opinion also confirms that prescribing medication is a core professional service for purposes of coverage analysis, even when the prescribing occurs in a context involving personal misconduct. Physicians facing administrative proceedings that blend professional and personal allegations can expect their insurers to shoulder the entire defense if any allegation relates to professional services.

Read the full opinion: O'Connor v. MAG Mutual Insurance Company (SJC-13821, August 7, 2026).