A new report is taking a look into New York State's prison system and reveals that state prison guards are often protected and rarely fired when accused of abusing people in their custody. 

The two-year investigation by the nonprofit newsroom, The Marshall Project, in partnership with The New York Times, shines a light on a culture of impunity behind bars.

Using thousands of court documents, arbitration records and officer disciplinary data, the reporters show that guards often work together in groups to cover up assaults by lying in official reports, and to investigators.

Alysia Santo, an investigative reporter at the Marshall Project, and one of the authors of the piece, joined Errol Louis on “Inside City Hall” Tuesday night to discuss the conditions inside state prisons.