Last week, the attorney for former New England Patriots tight end Aaron Hernandez announced he was filing a lawsuit after researchers discovered Hernandez had severe chronic traumatic encephalopathy, or CTE, a condition that develops in the brain as a result of repeated blows to the head.

Hernandez killed himself in April in his prison cell just days after his acquittal in a 2012 double-murder case. He had also been convicted of a separate murder in 2013 and was sentenced to life in prison without possibility of parole.

Hernandez’s attorney has filed a lawsuit against the Patriots and the NFL, claiming the team and league hid the true cognitive risks and dangers of playing football. The NFL recently agreed to pay $1 billion to retired players who suffer from CTE, but players were also given the option to opt out of the collective settlement and file their own personal lawsuits.

“I have never been very convinced of a player’s right to sue the NFL, but it was good public relations for the NFL to agree to pay out the settlement,” said sports law expert Roger Abrams, Richardson Professor of Law at Northeastern. “I have always thought that players should be considered to know those risks.”

CTE also made headlines recently after a study found the disease in all but one of 111 brains of former NFL players. Cognitive rehabilitation expert Therese Pirozzi, associate professor in the Bouvé College of Health Sciences, said she thinks it’s very likely that CTE affected Hernandez’s behavior.

“Some symptoms of CTE include substance abuse, suicidal thoughts and behaviors, personality changes, aggression, emotional instability, and memory loss,” Pirozzi said, adding that she expects lawsuits involving former players to become more frequent.

The lawsuit Hernandez’s attorney is filing will seek reparations for the former player’s 4-year-old daughter. His argument is that the NFL and the Patriots knew consistent head hits could cause CTE, hid the full extent of the danger, and didn’t do enough to protect Hernandez.

“There is some evidence the NFL hid certain studies and didn’t conduct the inquiries they should have,” Abrams said, adding that lawsuits will have to show there was a failure by the team to inform players of the potential risks. “Like I tell my students in class, you can argue anything. Whether the court will buy it or not is another question,” he said.

Pirozzi said players should fully participate in pre-season cognitive testing and alert the team’s medical personnel if they experience any signs or symptoms of a concussion, whether one has been formally diagnosed or not. From a research standpoint, doctors, scientists, and engineers have been working for years to understand and protect against CTE.

“Equipment-wise, there is research focusing on the design of football helmets to prevent the consequences of multiple concussions by measuring and reducing the impact of a hit,” Pirozzi said. “There is also a need for stronger evidence-based guidelines for when concussed players at any age and level of the sport should return to play and what they should or should not be doing prior to their return.”