Transcript for Why Aaron Hernandez Trial Is Poor Timing for NFL
young man with wealth and fame throw it all away? Aaron Hernandez was planning a future, not a murder. Reporter: The time timing of the trial could not be worse for the NFL. It has been a tough year. It's been a tough year on me personally. Reporter: Its biggest game of the year on Sunday, after an unprecedented season of scandal and scrutiny. Including the most recent defla deflategate allegation. I didn't believe Tom Brady. The balls were deflated. Reporter: Which call into question the legacy of one of the greatest coaching quarterback tandems in NFL history. Would not say that I'm Mona Lisa fido of the football world. Is Tom Brady a cheater? I don't believe so. Reporter: Now this trial will surely grip the nation. The former tight end who pleaded not guilty was 23 at the time of the murder. A rising star on the biggest stage. And the tuls -- Reporter: Even scoring a touchdown in super bowl xlvi. Touchdown! Hernandez! Reporter: Prosecutors play a different picture. Playing this surveillance video they say shows Odin Lloyd getting into a car driven by Hernandez shortly before his killing. This image of Hernandez standing outside his basement, holding in his left hand what the prosecution says is a gun. What the case won't include, text message records from oudin Lloyd the night of the murder, deemed ined a viable in court. There's a great deal of information the jurors won't see, won't hear. The texts. Did you see who I'm with? His sister answers, who? Lloyd answers, NFL, just so you know. What's the significance of that? "Just so you know." Prosecutors wanted to introduce that to say, he was warning his sister. I'm with the NFL guy, just in case anything happens. That would have been incredibly powerful evidence for the jury to see. And prejudicial. The judge ruled that it was too speculative to say that's why he was writing the text. This is not a slam dunk? I think most people watching this case think prosecutors can get a conviction here. But it may not be that easy. Reporter: In court, Hernandez sits well groomed, well dressed, his demeanor gives no indication of the trouble he faces or the trouble in his past. ESPN's Jeremy Schaap said there were concerns over Hernandez before he was drafted by the patriots. Aaron Hernandez became a fourth round rather than second or third round draft pick in 2010 because the league had looked into his background. And some people determined that they didn't like what they had seen. Reporter: Aaron Hernandez was raised in a tough neighborhood in Bristol, Connecticut. And he had his share of heartache. His father died when he was 16. And that was very, very tough for him at the age that it happened. Had a little bit of a tough upbringing. Both because of that and even before that. Reporter: Aaron Hernandez had one gift that made everything better. Football was something that he really loved. I think it gave him a little bit of a reprieve from maybe some of the other everyday challenges of life when he was around football, he could forget. Reporter: Even in high school it was clear he had an unusual talent and he started getting calls from colleges. Eventually getting recruited by the university of Florida. A bright future stretched before him, if he could only keep his demons at bay. He himself said that he had a history of getting into trouble. Reporter: Before he played a single game his career was almost sidelined forever. There are reports that airplane Hernandez had an altercation at a bar called the swamp. Reporter: A police report from the 2007 incident surfaced recently. Hernandez had gotten into a fight with the bar manager over two drinks Hernandez maintained he hadn't ordered. And guess who tried to come to his aid? According to the police report, college teammate Tim Tebow offered to pay for the drinks. Instead, according to authorities, Hernandez punched the manager so hard his eardrum burst. He could have been kicked off the team and he wasn't. Reporter: Hernandez was never charged with the assault and his career quickly took off. By the time he reached the NFL even he insisted he got it, he'd matured. You get changed by the patriot way. Now that I'm a patriot, I start living like one and making the right decisions for them. Reporter: In a league where winning is everything, NFL teams have been known to take chances on players with unquestionable talent and countless questions of character. Bill belichick, somebody who's always looking for a way to win. And I'm not saying that character isn't a factor in their decision-making. They've shown eagerness or at least willingness over the last years to take chances on guys who'd had serious run-ins or more minor run-ins but certainly not the first thing that gets considered when someone's signed. Not only by the new England patriots but by just about anybody. Reporter: For his part, bill belichick vowed to vet his players more closely in the future. After Hernandez's arrest. We learn from this terrible experience that we'll become a better team from the lessons that we've learned. Reporter: Tonight, not only is his character in question, so too is his freedom. Which he could lose for the rest of his life. Under the law, in Massachusetts, if you are part of a group of people who together are committing a murder, all of you are equally guilty of the crime. Reporter: If we needed a reminder how poorly timed this case is, the judge issued to the jury today giving them permission to watch the super bowl, but warning -- If his name or this case is mentioned on television screens or computers if you're watching it on computer or anything, just walk away. It's vitally important. Reporter: This Sunday, while some of his former teammates play for glory, the jury may be able to watch the game but Hernandez won't. He'll be in solitary confinement inside a seven foot by ten foot prison cell. I think this trial, people think about and they say, what a waste. This guy had everything. Why would he throw it all away?
This transcript has been automatically generated and may not be 100% accurate.