Aaron Hernandez's family sues NFL, Patriots amid CTE revelation

An attorney for former New England Patriots tight end Aaron Hernandez announced Thursday a $20 million lawsuit had been filed in federal court against the New England Patriots and the NFL on behalf of the ex-player's former fiancée, Shayanna Jenkins Hernandez, and the couple’s daughter.

The lawsuit was filed the same afternoon as it was announced that Hernandez had been diagnosed with chronic traumatic encephalopathy (CTE). 

The 18-page filing, a copy of which was obtained by USA TODAY Sports, contends both the league and team "were fully aware of the damage that could be inflicted from repetitive impact injuries and failed to disclose, treat or protect him from the dangers of such damage."

"We intend to contest the claims vigorously," NFL spokesperson Joe Lockhart said on a conference call on Friday.  

The lawsuit could face one major league hurdle: Hernandez was not listed among the players who opted out of a concussion settlement with the league.

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Players whose careers concluded before July 2014 "gave up the right to sue the NFL Parties" unless they opted out, according to the settlement. Hernandez's last NFL game was in January 2013 before he was arrested -- and ultimately convicted -- for the murder of former semi-pro football player Odin Lloyd.

“By not opting out, his daughter is now bound by the terms of the settlement," David S. Weinstein, a former assistant U.S. attorney and current partner at the firm Hinshaw & Culbertson, told USA TODAY Sports. "The NFL and Patriots have an easy road to dismissal."

While serving a sentence of life for Lloyd's murder, Hernandez was found hanged in his jail cell at the Souza Baranowski Correctional Center in Shirley, Mass., in April. His death at age 27 was ruled a suicide. 

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Boston University's CTE Center said in a news release that an examination of Hernandez's brain showed signs of an advanced form of the disease. CTE, which can only currently be diagnosed in an autopsy, can be caused by repeated head trauma and leads to symptoms like violent mood swings, depression and other cognitive difficulties.

"Aaron Hernandez succumbed to the symptoms of CTE," states the lawsuit filed in U.S. District Court in Boston. "As a result of the defendants’ conduct and the injury experienced by Aaron, Avielle Hernandez was deprived of the love, affect, society and companionship of her father while he was alive."

Patriots spokesperson Stacey James said team didn't have comment on Thursday.

“Not only were the results positive, but we’re told it was most severe case (BU) had ever seen for someone of Aaron’s age,” said Jose Baez, who represented Hernandez at his second murder trial, at a news conference on Thursday. “Aaron Hernandez had an advanced stage 3 of CTE, which is usually found in the median age of a 67 year old man."

Contributing: Kevin Spain, The Associated Press

PHOTOS: Aaron Hernandez throughout the years