I couldn’t find a U.S. Jewish statement on private prisons, but Tomer Zarchin
published this in Haaretz
in Israel 20 November 2009:

International legal precedent: No private prisons in Israel

The High Court of Justice put an end to years of controversy Thursday
by ruling that privately run prisons are unconstitutional.

Following the decision, the state is expected to have to pay hundreds
of millions of shekels in compensation to a company that had already
completed construction of the first private prison, near Be’er Sheva.

The panel of nine justices, presided over by Supreme Court President Dorit
Beinisch, ruled that for the state to transfer authority for managing
the prison to a private contractor whose aim is monetary profit would
severely violate the prisoners’ basic human rights to dignity and freedom.

-jsq