He was one of the most talented football players of his generation, and now he might live the rest of his life behind bars. Lawrence Phillips was a big-time star at Nebraska during the 1990s and was a first-round pick in the 1996 NFL draft.

Now, he's a convicted felon serving a 31-year sentence for assaulting his ex-girlfriend and trying to run over three teenagers with a car. And things could get worse: Phillips is a suspect in the death of his cellmate at a maximum-security prison.

USA Today has released letters Phillips sent to loved ones in the time period just before his cellmate was killed. Phillips describes the prison as a horrifying place in several letters sent to Ty Pagone, a former high school coach with whom Phillips has maintained a strong relationship.

"Coach D, this place is a jungle," Phillips writes. "Trouble everywhere. One must swallow his pride constantly or one will always be in the hole. But we must deal with the situation we put ourselves in."

In another letter, Phillips writes that he has been cleared to move from a max compound to a minimum security prison, but his move has been held up due to overcrowding. The prison currently housing him was built to handle 2,500, but its current population is more than 3,700.

In a May 2014 letter, Phillips says that he has applied to live in a single cell, citing the drug habits of other prisoners. Two weeks later, he says this about his social situation:

"All they they want to do is the drugs, make knives and make alcohol. Then they say when they get out they will not come back. I tell them of course you will. You are doing the same thing that got you locked up. Of course they do not want to hear that. It is like speaking to a brick wall.

"Now I understand how people must have felt talking to me. So needless to say I have zero friends inside here. Not one person is in line with my way of thinking."

In the last letter, Phillips alludes to a problematic situation he is facing in the prison, but does not go into detail. This likely refers to his suspected role in the death of his cellmate. Prison officials have only said that the investigation is ongoing.

It's a troubling latest development for the fallen football star, but also a sharp critique of America's prison system. If those feelings of fear, discomfort and paranoia were simmering for that long, can the system be all that surprised when its prisoners reach a breaking point?

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