Airline passengers have to deal with all manner of human menace — whether it’s that inconsiderate person in the aisle seat eating a tuna sandwich, the charming child repeatedly kicking the back of your seat while his parents pretend not to notice, or the dude next to you voiding his bladder on your leg. At what point does another passenger’s transgression become the fault of the airline?

A United passenger who says another traveler used his leg as a urinal during a June flight from Los Angeles to Newark is now blaming the airline in a lawsuit [PDF] filed in a New Jersey court accusing United of allowing a visibly drunk passenger to board the plane in the first place.

The plaintiff says that when he boarded the aircraft, he noticed the stranger in the next seat was “heavily intoxicated prior to entering the flight, and had fallen into a drunken stupor.” According to the complaint, “a powerful odor of alcohol was emanating from the passenger’s breath and body.”

The lawsuit states that just as the flight was preparing to take off, the man seated next to him took out his penis, aimed it at the plaintiff, and “proceeded to urinate all over [the man’s] leg” while he was confined to his seat due to the “imminent departure of the flight.”

Not only did his seatmate smell of booze, but “upon being soaked in the passenger’s urine,” the plaintiff says he noticed the stuff “also emitted a powerful scent of alcohol.”

“Shaken and disturbed by these events,” the man claims he tried to wake the other passenger up, but couldn’t because he was too drunk.

He says that no flight crew members had done anything to intervene throughout the experience. He notified a flight attendant and asked to be moved, “to avoid the continued humiliation, assault, and inhumane experience of sitting in urine-soaked clothes on a urine-soaked seat.”

The lawsuit claims United refused that request at first, but eventually relocated him to another seat. However, he was then “forced to endure the remainder of the flight” to New Jersey while remaining in his urine-soaked clothing.

The man says he got in touch with his father during the flight to let him know what happened, and that he then notified law enforcement. The lawsuit claims that if he and his father hadn’t contacted police, no one would have intervened.

Upon arrival, both men were removed from the plane and interviewed. The complaint claims that during an FBI interview, the allegedly intoxicated passenger said he didn’t remember anything from the flight, and only recalled being at a bar inside LAX.

He believed he’d consumed at least four rum cocktails while at the airport bar prior to the flight, the lawsuit says.

The passenger’s “unresponsive state upon being seated should have been a clear indication to United of the passenger’s heavy intoxication,” the passenger’s lawsuit claims.

“United failed and refused to change the flight itinerary as a result of the assault and thus risked the health and safety of not only” the passenger who’s suing, but the man accused of peeing on him and other people on the flight.

The complaint points to United’s own contract of carriage, which requires that members of the crew remove passengers who “appear to be intoxicated or under the influence of drugs to a degree that the passenger may endanger the passenger or another passenger or members of the crew.

The lawsuit alleges negligence and assault, as well as breach of contract and emotional distress.

We’ve reached out to United for comment on the lawsuit and will update this post if we receive a response.

The anonymous passenger accused of urinating on the man’s leg is also named as a “John Doe” defendant in the case. He’s accused of assault and battery, negligence, and negligent infliction of emotional distress.

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