I think the Chicago cops were keenly aware that if this wasn't solved, the liberals wouldn't hesitate to excoriate them. Unfortunately for the liberals, the cops did their job well. The cops presented a prosecutable case, and that's not exactly what the liberals wanted. So, corruption was their fallback.
I’m sure there are many people, including the FBI, digging into this blatant miscarriage of justice. The truth of who planned this hoax and who pulled the strings on this will be discovered. There are too many Americans outraged over this for it to be not be exposed. The extreme arrogance on the Left will be their undoing.