Who's ultimately responsible? Hey, if they actually investigated that

it would cause problems for the Party.  And they can't have that.
But the politicians — meaning Lynch and Emanuel and others — protected themselves by ignoring the most important aspect of Chicago police culture.

It wasn't the Chicago cops who shaped the police culture. The political corruption and cynicism of politicians over decades in a one-party Democratic machine town shaped the culture.
Police are just part of that culture. They're the part with guns.

So all that was shaped by City Hall, by Emanuel's predecessors, mostly. And now Chicago is paying for it.
Someone did ask, for what good it did.
Lynch was asked about the enablers of the police culture, the mayor's office, the city Law Department and the local prosecutors. She dodged that one.
Of course she did.  All the bigshots in control are Democrats.
"We are one Chicago with one goal," Emanuel said. "It is my fervent hope that this report doesn't lead to another round of finger-pointing or more acrimonious debate of us vs. them."

What he didn't say was that if there was any finger-pointing to be done, fingers should point at City Hall.
Of course not; that would point at him and the Party.