Laquan Mc Donald and Jason Van Dyke

After the video of the Laquan McDonald shooting was released in November, it was discovered that as much as 80% of the department's dashcam footage was missing audio.

"To boil this down, the police department will not tolerate officers maliciously destructing equipment", police spokesman Anthony Guglielmi told DNA Info.

At the very least, you could characterize the actions of the police department and officers involved as willfully negligent. The CPD has blamed the failures on "operator error or in some cases intentional destruction", and a close reading of that review by DNAinfo Chicago reveals the extent of the latter.

The records show that the dashcam in Van Dyke's vehicle, 6412, was repaired on 17 June 2014, about three months after it was reported broken.

Of the five police vehicles that were present the night of the shooting, only two had dashcams that actually recorded video, and one of those was reportedly broken.

Defense attorney Dan Herbert said Friday that if the device was tampered with, then someone other than his client was responsible. He has pleaded not guilty to first-degree murder in McDonald's death.

If Laquan McDonald's death at the hands of Chicago policeman Jason Van Dyke hadn't been recorded on dashcam video, Van Dyke, like countless officers before him, might never have been arrested or charged with murder.

Chicago Police officer Jason Van Dyke killed LaQuan McDonald and attempted to destroy the evidence.

In fact, on the night of McDonald's shooting, out of the five dashcam-equipped cop cars at the scene, only two recorded video, and out of those two, only one had a working microphone to capture audio. Video of the shooting was released last month, sparking a wave of protests.

The release of the video ignited citywide outrage, with demonstrators expressing anger that it took city officials 13 months to charge the officer, who remained on paid desk duty during that time.

Such dogged commitment to maintaining a lack of transparency is a big reason why people in Chicago are so fed up with their police.

Chicago public health, fire, police and emergency officials will collect data about mental health incidents to help improve responses.

Prosecutors on Friday turned over to Van Dyke's lawyers documents from the Independent Police Review Authority, which investigates police shootings.

A 2014 investigation by the Los Angeles Police Department found that officers in that city removed antennas from their cars in Black communities.

Take the case of the Chicago officer who shot and killed Laquan McDonald. Van Dyke's lawyer has said the officer feared for his life.

The release of the video sparked citywide demonstrations with protesters alleging a cover-up and calling for the resignations of Mayor Rahm Emanuel and Cook County State's Attorney Anita Alvarez.

The police department's maintenance logs show scores of instances when in-car camera systems didn't function as a result of mechanical problems - and dozens of other occasions when police failed to use the equipment properly or disabled it on objective.