Lotta people here talking like they understand Chicago politics.
The people who investigate these incidents were appointed to investigate them because City and State agree'd that CPD was unwilling to investigate the misdeeds of their department.
So they setup an Independent review board. Which sounds nice and independent but...(Mayor and CPD friends filled it with former CPD brass or family of former CPD or former consultants to CPD)
Now they are firing investigators because they don't give reports that appease the department.
This is just another feather in the hat of police corruption rolling thru Chicago.