The widow of a Metro employee who used the transit system to kill himself is suing the agency, saying it did not stop him from jumping in front of a train after he made an earlier attempt the same day.

Yvette Thomas is seeking $1.5 million in her lawsuit transferred to U.S. District Court for the District of Columbia, charging that Metro was negligent in preventing the suicide of her husband Kurtland Johnson -- and by extension others -- on its property.

At least 15 people, including Johnson, have used the transit system to kill themselves within the past 18 months -- about five times the rates of the past. Meanwhile, Metro has delayed implementing a suicide prevention program that it announced in September.

Metro has asked for the suit to be dismissed, arguing that case law dictates that the transit agency cannot be held responsible for failing to stop those intent on killing themselves.

Metro declined to comment further on the lawsuit.

"It's a touchy subject," spokesman Reggie Woodruff said. "We of course feel terrible that the person, former employee killed himself."

Johnson was placed on paid leave in September 2008 after his bus was involved in a bump up with another vehicle. Such leave is standard while Metro investigates a crash. But he was "very distraught," the suit says, and Metro was aware of his emotional state.

On March 13, 2009, he sat on the Farragut West station platform and dangled his feet over the edge before climbing down onto the track bed and hugging the third rail. A station security camera captured the images, including Johnson climbing back onto the platform, the suit says.

About eight hours later, Johnson jumped in front of an incoming train at McPherson Square, one stop away. He died at the scene.

His widow's suit says the agency was not only aware of his emotional state but also should have known about the earlier attempt. It says the agency has "a duty to insure the safety of all patrons or visitors."

Metro has asked the court to dismiss the case on three grounds, including that it was filed after a one-year statute of limitations. But the primary reason is that a U.S. Appeals Court decision on a 1986 suicide found Metro could not be expected to save Devora Johnson, who also jumped in front of an incoming train.

Thomas' attorney, Lathal Ponder Jr., did not return a call for comment.