UPDATE: Lorenzo Davis is not able to join "Chicago Tonight" on Thursday. We will share rescheduling information when and if it becomes available.

Long before the death of 17-year-old Laquan McDonald, questions were being raised about how the city investigates police-involved shootings.

The city's Independent Police Review Authority is tasked with handling those investigations. But since its creation in 2007, IPRA has probed about 400 police shooting investigations and found only two to be unjustified.

One former IPRA investigator in July told WBEZ he was fired because he would not change his reports to support police officers. That would be Lorenzo Davis, who served as a police commander before joining IPRA in 2008. He joins us tonight to talk about the code of silence within the police department and what he saw at IPRA during its investigation of the McDonald shooting.

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