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California prisons, such as Mule Creek State Prison in Ione will be forced to reduce population sizes following a U.S. Supreme Court ruling.

Following four weeks of hunger strikes from inmates at Pelican Bay and three other California detention facilities, the state has not put into practice recommended reforms for its isolation units. Former New York City Corrections Commissioner Martin Horn teaches at John Jay College of Criminal Justice. He joins Madeleine to discuss how California's isolation units are the most punitive in the country -- and why the reasons prisoners get sent there are different from other states.

Horn said prisoners can be put in Special Housing Units for gang affiliations as a preventative measure, rather than as a punitive measure for specific acts committed. He said the overcrowding problem in California prisons, resulting in large, understaffed dorms, rather than individual cell blocks, creates an environment in which inmates are often driven to join gangs for their safety.