The ideal of a penal imprisonment is criticized by many reformers because
1. it is incapable of corresponding to the specificity of crimes
2. it has no effect on the public
3. It is useless, even harmful to society: it is costly. it maintains convicts in idleness, it multiplies their vices.
4. the execution of this penalty (imprisonment) is difficult to supervise
5. There is a risk of exposing prisoners to the uncontrolled power of the guards
6. The job (prison guard) is an exercise of tyranny (dictatorship)