A Metro rider is seen in front of an approaching train at the Judiciary Square station on Jan. 9, 2012, in Washington, D.C. (Matt McClain/The Washington Post)

The family of a D.C. man who fell in a Metro station and suffered a fatal head injury has sued the transit authority for alleged negligence because the man’s body went undiscovered for four days.

If Metro workers had been more alert and come quickly to the man’s aid, he might have survived, the lawsuit contends.

However, a person familiar with the incident — speaking on the condition of anonymity Tuesday because of the pending litigation — offered a more detailed account of the 2013 accident than the version given in the lawsuit, filed in D.C. Superior Court.

The person said that Okiemute C. Whiteru, 35, whose family is seeking a multimillion-dollar award, was alone and intoxicated in the Judiciary Square station late at night when he sat atop a three-foot-high wall at the rear of the platform.

On the other side of the wall is a trenchlike well, eight feet deep, that runs the length of the station.

Whiteru lost his balance and fell backward off the wall, striking his head, according to the individual, who has viewed surveillance video of the incident. He said Whiteru apparently was rendered unconscious in the fall. He hit the bottom of the well and rolled beneath the platform, where his body was out of sight.

An autopsy later found that Whiteru, a lawyer who lived in Southeast Washington, was heavily intoxicated that night, the person said.

The lawsuit, filed May 1, says the incident happened Oct. 19, 2013, when Whiteru “lost his balance” and “fell a short distance” off an escalator in the Judiciary Square station.

The individual with knowledge of the incident and who viewed the video said no other customers were in the station as Whiteru rode down an escalator toward the platform while struggling to stay on his feet.

The video shows him stumbling several times on the escalator but not falling off, according to the person. When Whiteru reached the bottom of the escalator, he stood for a moment, wobbling, then fell to the platform and had trouble getting up, the person said.

The lawsuit mentions none of that. It says that after Whiteru “fell from the escalator,” he was “attempting to collect himself” when he “fell backwards, and dropped a distance of eight feet, resulting in incapacitating injuries.” It offers no more details.

The person who viewed the video said the eight-foot plunge came after Whiteru, who was having difficulty standing, decided to sit atop the wall instead.

As for Metro’s alleged negligence, the lawsuit says that “despite actual knowledge” of Whiteru’s fall, transit employees “failed to recognize and investigate the happening of the fall, or otherwise respond to the occurrence, such that [Whiteru] remained, in his injured state, undiscovered” for four days.

Metro workers are to blame for the fact that Whiteru “succumbed to his injuries and died a tragic, painful and untimely death,” the lawsuit says.

However, the person familiar with the incident said, no Metro workers saw Whiteru fall, and surveillance video is reviewed only after a known incident occurs. In this case, he said, the video was not looked at it until after the body was found and an investigation was conducted.

The person with knowledge of the incident said that after Whiteru’s body rolled under the platform, thousands of commuters passed through the station for four days and three nights, without a report of a body. He said that each night before closing the station, a manager signed a sheet attesting that the station had been checked for any lingering people.

Finally, the person said, someone noticed “an item” in the well, perhaps a scrap of clothing, and decided to take a look. Whiteru was far enough beneath the platform that his body was removed not through the well but through a platform manhole, the person said.

The lawsuit was first reported Saturday by the Washington City Paper.

The family’s attorney, Louis G. Close, of Towson, Md., was out of state Tuesday and not available to be interviewed, his office said. He did not respond to e-mailed questions. Whiteru’s father, the named plaintiff in the case, could not be located for comment.