Turning to one mother's fight against an nfl team. The family of linebacker jovan belcher has filed a lawsuit against the kansas city chiefs. He murdered his girlfriend and committed suicide a year... See More
Turning to one mother's fight against an nfl team. The family of linebacker jovan belcher has filed a lawsuit against the kansas city chiefs. He murdered his girlfriend and committed suicide a year ago. The mother says were it not for the team, her son would be alive today. Abc's ron claiborne has the story. Reporter: This morning, the kansas city chiefs are facing a lawsuit, accusing them of ignoring signs of brain damage, suffered by jovan belcher and pressuring him to play when he should not have. And it goes a step further. Seeking the blame of his 2012 suicide on the team's alleged negligence. They hit on something new. That's the wrongful death claim. Reporter: In december of last year, the 25-year-old belcher shot and killed his girlfriend, 22-year-old kassandra perkins, in front of their 3-month-old daughter, before driving to the team's practice facility and killing himself. Now, belcher's mother is bringing a lawsuit, saying the repeated blows to his head in his four years with the chiefs, caused him to suffer severe headaches, depression, mood swings, suicidal idealations. It also says he didn't get proper medical care after two concussions. Instead, it says the team berated him and bullied him to play through his injuries. If they can prove that there's permanent damage to his brain because of concussion and because of practicing and playing the game, that takes them a long way to proving what happened. Reporter: The kansas city chiefs told abc news, they are aware of his family's lawsuit. But would not comment. Belcher's body was exhume to undergo medical tests as part of his family's effort to prove he suffered brain damage from playing football. And the medical tests are key to the family's lawsuit. They need to prove that belcher was permanently brain damaged from playing football. And more, that that was the reason he killed himself. Amy, the lawsuit against the chiefs does not specify a dollar figure. They're hoping the jury will set that. Much more to come in time. Ron claiborne, thank you.
This transcript has been automatically generated and may not be 100% accurate.