A truck driver was recently killed in an accident on Grand Avenue in Queens, New York, after striking a street pole. Police suspected the man had a medical episode while behind the wheel, which ultimately led to the fatal accident. The accident occurred just hours after another trucker was killed a mile down the road when a woman lost control of her Chevy sedan and swerved into oncoming traffic. Police were unsure what caused the woman to lose control. The pair of tragic accidents raise a complicated legal question: If one or both accidents occurred as a result of a heart attack or similar medical event, is anyone to blame?

Under normal circumstances, if a driver swerves into oncoming traffic and causes a crash, they would at least be liable in civil court. They would owe damages in a personal injury or wrongful death case, depending on the amount of harm they caused. When a driver is negligent or reckless, and that behavior leads to an accident, the driver is responsible for the resulting damage. If they swerved intentionally, they might even be criminally liable for vehicular assault or homicide.

If someone has a heart attack while driving, however, it’s tough to say that they “caused” a resulting accident, in the legal sense of the word. Their physical actions caused the crash, but their actions were involuntary. If someone else grabs the hands of a driver and causes a crash, that other actor would truly be to blame, even though the driver’s hands were on the wheel. People are not usually held liable for matters outside of their control.

On the other hand, under certain circumstances, even involuntary behavior can give rise to liability. If a drunk driver (or even a sober driver) falls asleep at the wheel, for example, and they crash into another driver, the driver is surely to blame. It’s no defense that the driver did not choose to fall asleep, nor did they choose to keep their feet on the pedals or move the steering wheel while unconscious. The law holds drunk drivers and drowsy drivers liable because they chose to drive while in an unsafe state of mind; getting behind the wheel was their true wrongful act, which ultimately led to the crash.

Where does a medical emergency fall on the spectrum of voluntary vs. involuntary conduct? It depends. In most states, there is a defense to driver liability for a “sudden medical emergency.” Like being pushed in front of a car by someone else, having a sudden heart attack is hardly within your control. If you have a heart attack, a stroke, or some other medical emergency while behind the wheel, you are not truly responsible for what happens next.

New York personal injury attorney Leandros A. Vrionedes confirms that the “medical emergency doctrine” is well settled in New York. “An automobile driver who experiences a sudden medical emergency will not be considered at fault for causing an accident due to the emergency,” he says, “so long as the medical emergency was unforeseen.” Although there is no statute in New York creating the medical emergency doctrine, Vrionedes explains that numerous cases in New York’s highest appellate courts have upheld the doctrine.

The rub, however, is that the accident must truly have been outside of the driver's control. Drinking and driving is illegal because it creates an unacceptable and foreseeable risk of an accident. If a driver knew they were at risk of a medical emergency then, arguably, they had no business getting behind the wheel. The driver was putting others on the road at risk of injury or death just the same as if they were driving while intoxicated or while ready to fall asleep.

Attorney Vrionedes also describes other situations where the emergency doctrine might apply without a medical emergency. He points to the scenario where a pedestrian suddenly darts into the roadway or when a car ahead suddenly stops for no reason, forcing the driver to swerve out of the way and hit another vehicle. Drivers must still react reasonably to sudden emergencies on the road; if they overreacted and caused a crash, they might be considered at least partly responsible for the accident.

Legal liability in these situations often turns on the critical question of foreseeability, which is a required element of the doctrine in New York as attorney Vrionedes pointed out. Was the incident truly sudden and unexpected, or should the driver have foreseen the risk of the emergency? Answering this question requires a thorough understanding of the applicable law, although the precise facts in each case will be determinative as well.

Edge cases can become even more challenging. What constitutes a foreseeable risk of a medical emergency? Should everyone with a pacemaker be barred from driving? The answer turns on the confines of the law as dictated by the legislature and the courts of each jurisdiction. Whether you are trying to prove that the driver was or wasn’t at fault, you’ll likely need the help of an attorney who is knowledgeable about the emergency doctrine and applicable case law in your state.