The bottom line is that a man was assaulted and battered by a malicious person who was not acting with any privilege, self defense or otherwise. Our prison system needs reform badly. Though it's not supposed to be a jolly good time, and I can assure you from personal experience that it is not a good time, we also should not subject people to being beaten, killed, or raped. If a cop did this to Donaghy, it would be headline news and the cop would get burned in effigy. However, we're willing to chalk up this tragedy to "that's just how prison is, that's what he gets." No, that is unacceptable.
Prison is not just a punishment, it is a mechanism to attempt to rehabilitate offenders and return them to productive life. People make mistakes, bad ones. Hell, the criminal justice system makes mistakes, bad ones. These people do not deserve to be subjected to beatings, rape, or killings. We are locking these offenders into cages, taking away years of their life, breaking up families, ruining future employment prospects. Don't tell me we ought to let them get beaten, killed, or raped on top of all that.
The mark of a civilized society is that we do not endorse or allow such brutal behavior. Look, punishment does not restore anything. If a murderer is incarcerated, he is completely deterred from committing that crime (against general society) for the duration of his sentence. The idea here is to prevent him from killing anyone else for the duration of his sentence, to deter him from killing in the future after release, and to serve as a general deterrent that would be offenders might consider their actions before killing. However, all of that will not bring a dead man back. All of that won't dry one single tear, (though it may prevent some tears). You can't tell me that allowing a man to be beaten, killed, or raped serves ANY good purpose whatsoever. It's a damn tragedy and anyone who thinks otherwise is a sadist IMO.