Five Teito Rapid Transit Authority employees who were in charge of maintenance at the time of a deadly train crash last March were accused of professional negligence on Tuesday as police handed the case over to prosecutors.

It is the first criminal action taken by investigators into the accident, in which five Hibiya subway line passengers were killed when the last carriage of an eight-car train derailed and sideswiped a commuter train running in the opposite direction on a parallel track near Nakameguro Station.

Tokyo police determined that the five maintenance officials, who were not identified, failed to properly maintain the tracks and, as a result, created one of the factors that led to the collision.

Of the five men, aged between 47 and 61, one has since retired.

However, they opted not to summon Teito’s top officials before prosecutors because they were not in a position to be informed about the potential problems regarding the tracks, which investigations have shown were a key factor in the tragedy.

Investigations after the accident showed that the gauging of the track at the scene of the crash did not meet Teito’s maintenance standards.

In addition, during some maintenance work, the surface of the rails had been ground down as much as five times the amount initially planned.

Police determined that various factors led to the derailment, but said proper maintenance of the tracks could have prevented the accident.

According to investigators, Teito gauged the rails in November 1999.

As a result, 13 spots along the roughly 30 meters of track near the site of the derailment registered discrepancies exceeding the operator’s standards by a few millimeters.

Although two of the Teito maintenance officials saw documents on the gauge discrepancies, they took no corrective action, police officials said.

In an effort to alleviate noise, Teito also planned to grind a maximum of 0.2 mm off the top of the rails in December that year.

However, the three other officials sent to prosecutors were not fully aware of the specifications of the machines used by the firm contracted to do the work, and in some locations as much as 1 mm was ground off the rails. These officials failed to confirm whether the job had been done properly, police said.

As a result, the alleged negligence of the five led the subway car to derail and hit the other train, leading to the five deaths and scores of injuries, police said.

The two accused of doing nothing to correct the warped rails have told investigators they opted not to do anything because another round of maintenance work had been planned for April — a month after the accident occurred — but admitted that the matter should have been dealt with more quickly, according to sources close to the case.

In October, the then Transport Ministry drew up a final report on the causes of the accident and detailed steps to improve safety.

Although the ministry’s report says the most significant factor behind the collision was a load imbalance between the right and left wheels of the subway car, the car was too seriously damaged to be used as evidence to press for criminal liability.

Investigators had been poring through the evidence to see whether any other factors behind the crash could be used to identify anyone else who might be held criminally responsible.

Kunihiko Tomihisa, the father of 17-year-old Shinsuke Tomihisa, who died in the accident, told reporters Tuesday that while he is grateful for the police effort to bring the case to court, he was still angry at the lack of priority both the subway operator and the Transport Ministry placed on safety.

“It is indescribably mortifying that criminal liability will not be pursued against officials at the Transport Ministry’s Railway Bureau or the top officials of Teito, who are mostly people who have parachuted down from the bureaucracy,” he said.

In a time of both misinformation and too much information, quality journalism is more crucial than ever.
By subscribing, you can help us get the story right.