Penitentiary: Let's look closely at that word. Of course, it means a place of corrections/prison, but let's look at the root word, penitent. Penitent refers to expressing sorrow for one's mistakes. Taking that forward to the word "penitentiary", then, it would be reasonable to infer that a penitentiary is "a place for those who are contrite," or "a place to make people contrite."
The reason I made the above point is that a friend suggested that prisons should be only to incarcerate those who pose a continuing threat to society. I could scarcely disagree more. Forty-six young men were vilified in the national press, had their basic civil rights abused in a manner reminiscent of the Scottsboro Boys during the days of segregation, and they had their physical safety threatened as a direct result of the words and actions of people in power at Duke University, the Durham District Attorney's office, the Durham Police Department, and various media entities. My friend mentioned prison overcrowding as a reason for his stance. Fine. Free those whose only "crimes" harmed themselves. Free everyone who's in prison for drug possession and selling, and free those arrested for prostitution and soliciting prostitutes. However, whenever such abuses occur as we saw here and with the West Memphis Three, justice must not only be done, it must be seen to be done. Prison is not simply for incarcerating those who are a continuing danger to society. It is for those who, through their criminal acts, have caused serious harm to others. Also, especially in this type of case, it serves as a warning and deterrent to those who would follow their example. In that latter case, it is, literally, to make an abuser of their power penitent. Society suffers as a whole when those who abuse their power, be they priests, prosecutors, police officers, professors, etc., do not face justice or are not seen to be facing justice. It is for that reason that I advocate a long prison sentence for anyone found guilty of such abuses, because without faith in the system, without a reason for people to have faith in the system, society suffers, and those wounds take decades to heal, if ever.