Mistaken prison releases are rare - State and county jails across Pa. have few such incidents, but Delco has had at least 5 since May

Lancaster County prison officials use an iris scanner to identify inmates so there is no mistaking who walks out the door.

In Bucks County, a supervisor triple-checks paperwork to avoid errors; Montgomery County requires at least two corrections officers to discharge a prisoner.

In Chester County, inmates wear photo identification cards.

Even with those measures, wardens say mistaken releases happen, though rarely - no more than one a year from each county jail.  Read More...