Boies in "Prisoners and Paupers" suggests life-long isolation. He
says:--"It is time however that society should interpose in this
propagation of criminals. It is irrational and absurd to occupy our
attention and exhaust our liberality with the care of his constantly
growing class, without any attempt to restrict its reproduction. This is
possible too, without violating any humanitarian instinct, by
imprisonment for life; and this seems to be the most practicable
solution of the problem in America. As soon as an individual can be
identified as an hereditary or chronic criminal, society shall confine
him or her in a penitentiary at self-supporting labour for life.

Every State should have an institution, adapted to the safe and secure
separation of such from society, where they can be employed at
productive labour, without expense to the public, during their natural
life. When this is ended with them, the class will become extinct, and
not before. Then each generation would only have to take care of its own
moral cripples and defectives, without the burden of the constantly
increasing inheritance of the past. When upon a third conviction the
judicial authorities determine the prisoner to belong to the criminal
class, the law should imperatively require the sentence to be the
penitentiary for life, whatever the particular crime committed."

M. Boies defines a criminal as one in whom two successive punishments,
according to law, have failed to prevent a third offence.

If such a criminal is a woman, she should be offered the alternative of
surgical sterility or incarceration during the child bearing period of
her life; if a man, his wife should be offered this remedy against the
procreation of criminals in exchange for her husband, on the expiry of
his sentence, or the protection of divorce.