The murder case against Chicago police officer Jason Van Dyke is pretty straightforward, and contained almost wholly in the seven-minute dashcam video where he’s seen firing 16 shots at 17-year-old Laquan McDonald, despite the absence of anything resembling a threatening advance from the teenager. The shots continue as McDonald rests in a fetal position on the ground, with Van Dyke even stopping to reload before a colleague intervenes.

A political case (if not a criminal one) against the Chicago power structure, right up to Mayor Rahm Emanuel, is just as clear-cut. The police first lied about the incident, saying the victim was “going at one” of the officers with a knife. At a nearby Burger King, 86 minutes of potentially damning security camera footage “mysteriously” disappeared; Chicago police officers were seen at a security-system terminal shortly after the killing.

Afterward, the city rushed through a preemptive $5 million settlement with McDonald’s family that included a clause to keep the video a secret. The deal was approved by the city only days after Emanuel secured a close reelection victory, and was done with no public comment nor debate in the city council. When journalists started asking questions about the shooting and went to court to force a release of the dashcam footage, Emanuel’s lawyers and the Cook County prosecutor fought to keep it secret. They were successful for 13 months until a judge finally ordered that the tape be made public, and only then was Van Dyke named publicly and charged.

In short, “there’s been a cover-up in Chicago,” as former University of Chicago law professor Bernard Harcout wrote in a New York Times op-ed Tuesday in which he called for Emanuel’s resignation. The cover-up is clear to those paying attention, including activists in Chicago, who are uniformly demanding Emanuel’s resignation.

And yet, despite employing a police commissioner who engaged in a brazen cover-up, and despite going to court to keep a pretty obvious homicide a secret, Emanuel has enjoyed baffling immunity from criticism from just about every elected Democrat outside the city of Chicago.

The exception is a small handful of prominent black members of the House of Representatives, like Jim Clyburn of South Carolina, who told The Hill, “It’s pretty obvious to anybody that there is some cover-up taking place here.”

From pretty much everybody else in the party, there has been silence.

None of the major presidential candidates—who have spent the better part of a year embracing the Black Lives Matter movement and decrying police brutality—have even timidly called out Emanuel’s blazing misconduct in the case, let alone asked for his resignation. Hillary Clinton’s initial statement on the shooting  didn’t so much as allude to a year-long cover-up. She has since voiced support for a federal investigation into the shooting death, which Emanuel opposes, but has otherwise not broken with the mayor. Emanuel said Wednesday that he is “pretty confident” he still enjoys Clinton’s support.

President Obama’s statement also didn’t address the cover-up. Senator Bernie Sanders has been silent on the mayor’s role in the McDonald case, which is particularly odd given he’s been a longtime critic of Emanuel.

It’s hard to imagine this being the case if Emanuel were a Republican. Pretend that Florida Governor Rick Scott, a two-term conservative governor of a key swing state and a frequent Democratic punching bag, had similarly aided state troopers in covering up a police killing. Or imagine a presidential candidate like Chris Christie did it. While impossible to prove the hypothetical, it seems certain that leading national Democrats would have pilloried Christie relentlessly and demanded he resign.

That criticism and demand for accountability would have been fair and appropriate—it would arguably have been the most helpful thing prominent Democrats could do in a situation like this. While they can’t personally prosecute offending officers, they can create serious political consequences for other leaders that facilitate and enable a racist and violent system of policing.

But no political consequences for Rahm appear to be forthcoming, at least not from his Democratic colleagues. For different reasons—namely, a disinclination to mount a serious fight against police brutality—leading Republicans won’t go after Emanuel either, thus giving him a free pass from both sides. That’s a shame, because the mayor is already teetering on the brink of political collapse and exhibiting all of the signs of a politician whose tenure is in critical condition: scapegoating his police commissioner (after a long and telling period where he refused to do so), canceling scheduled visits, and sniping with reporters. One nudge from the likes of Hillary Clinton, and Emanuel would surely be headed to an early retirement.

Republicans, and particularly conservative media figures, like to portray Democratic crusades against police brutality and their embrace of Black Lives Matter as a crude and insincere play for votes. That criticism is now in danger of being validated. If you want people to know you care about police brutality, you have to demonstrate that you care even when “your team” needs to be held accountable. Otherwise, everything else you say on the subject is rendered insincere.