When a prison guard latches some worker caught behind bars to a pole or puts him or her on a chain gang, or when the state forces someone to hang a sign in their yard, it is a dehumanizing experience. It is part of the rulers' ideological offensive to break workers' confidence and sense of self-worth, while numbing other workers' solidarity. The rulers want to divide workers by convincing us that those convicted of crimes are guilty now and guilty forever. Creating a climate of eroded solidarity opens the road for cops to brutalize workers, frame them, brand them as criminals, and send them to prison or to death.
This treatment is reserved overwhelmingly for the working class. John E. Du Pont, currently facing murder charges, won't be facing any "hitching posts." This member of one of the top ruling families is currently in a psychiatric hospital, where he reportedly continues to conduct his regular business activities.
The right to be "free from cruel and unusual punishment" was an important democratic gain codified in the Bill of Rights, one that the working class has the most stake in defending. When a worker is convicted, sentenced, and completes his or her sentence, it should be put behind them, and they should be able to go on with their lives. Alienation of fellow workers, inhumane torture of prisoners, and holding guilt over someone's head after they've done their time - these are concepts alien to the proletariat that should be thoroughly rejected.