Here is a rundown of his legal troubles off the field leading up to his death.
June 17, 2013: Friend murdered
Odin Lloyd, a semi-professional football player, was found shot dead in an industrial park one mile away from Hernandez’s home in North Attleboro, Massachusetts.
Lloyd was dating Shaneah Jenkins, the sister of Hernandez's then-girlfriend Shayanna Jenkins. Hernandez went to high school in Bristol, Connecticut, with the Jenkins sisters.
June 26, 2013: Charged with murder
Hernandez's biggest legal saga started to unfold in the middle of 2013, when he was arrested at his home for the murder of Lloyd.
Following the arrest, Boston police reopen a double murder case that happened in 2012 and that they said may be connected to Lloyd's murder.
May 15, 2014: Charged with two other murders
Hernandez is indicted on two counts of first-degree murder in the shooting deaths of Daniel de Abreau and Safiro Furtado on July 16, 2012, as well as three counts of armed assault with intent to murder and one count of assault and battery by means of a dangerous weapon.
An attorney for de Abreu's and Furtado’s families said words may have been exchanged between the two men and Hernandez during a night out in Boston two years prior.
Police say de Abreu and Furtado, along with three passengers, were stopped at a red light in Boston’s South End, when de Abreau, the driver, and Furtado were shot to death by someone in a silver SUV with Rhode Island plates.
Boston police say they have the gun and the vehicle used in the shooting, though no motive has been given.
De Abreau and Furtado are not believed to have any ties to Hernandez prior to a chance encounter that same night at Cure Lounge, in Boston’s Theater District.
Shortly after Hernandez was charged with Lloyd's murder, police searched his uncle's home in Bristol and seized a silver car with Rhode Island plates, which matches the description of the vehicle that is believed to have been used in the murder of de Abreau and Furtado.
Jan. 9, 2015: Lloyd trial begins
Hernandez goes on trial for the murder of Lloyd. ABC News sources confirmed that prosecutors believe Lloyd was killed over his knowledge of the 2012 double-murder, but prosecutors were barred by the judge from telling the jury their theory for the motive because it was deemed speculation.
April 15, 2015: Hernandez convicted
Hernandez is convicted of first-degree murder in the killing of Lloyd, which carries a mandatory life sentence.
For a period of time after the conviction, Hernandez was held at MCI Cedar Junction, a prison about a mile away from the stadium where he once played for the Patriots. While at MCI Cedar Junction, Hernandez was slated to earn 50 cents an hour making license plates as part of a work program at the facility, according to The Boston Globe.
Feb. 14, 2017: Double murder trial begins
Hernandez goes on trial for the 2012 murders of de Abreu and Furtado in Boston.
April 14, 2017: Hernandez acquitted
After a week of deliberations, the jury decides to acquit Hernandez of the 2012 murders. Hernandez cries when the verdict is announced.
April 19, 2017: Found dead
In the early hours of April 19, the same day that his former teammates are visiting the White House in celebration of their latest Super Bowl win, Hernandez is found hanged in his cell at the Souza Baranowski Correctional Center in Shirley, Massachusetts. He is later pronounced dead at the UMass-Leominster hospital.
ABC News' Meghan Keneally contributed to this report.