U.S. Justice Department officials have made 86 different requests seeking mountains of information from City Hall regarding their investigation into whether Chicago Police officers might be engaging in practices that violate the Constitution or federal law, according to documents obtained by NBC5 and shared with the Chicago Sun-Times.

The feds’ wide-ranging requests focus on issues that have surfaced after the fatal police shootings of black teenagers Laquan McDonald, who was shot 16 times by an officer now facing murder charges, and Quintonio LeGrier, who appears to have been struggling with mental-health issues when he was shot by an officer during a domestic disturbance.

Authorities also appear to be seeking information on whether a “code of silence” exists within the Chicago Police Department that keeps officers from facing potential disciplinary action.

Additionally, they’re seeking a variety or records related to the Independent Police Review Authority, which investigates shootings by police officers and disciplinary complaints against them. Mayor Rahm Emanuel recently announced he plans to replace IPRA with “a new civilian investigative agency that has more independence and more resources to do its work.”

The feds have been seeking records from the city since Dec. 30, according to the documents, obtained by NBC5 under the Illinois Freedom of Information Act. Most recently, on April 18, officials sought information on police SWAT team and canine-unit deployments.

Many of the requests seek records dating back to Jan. 1, 2011.

The court-ordered release last year of a video showing Officer Jason Van Dyke shooting McDonald as the 17-year-old was walking away from him helped prompt the federal investigation. Since the video’s release, Emanuel has fired police Supt. Garry McCarthy and faced a barrage of criticism on everything from lax police disciplinary practices to police dashcam videos having no audio of incidents they record.

The mayor also might be called to testify in a federal whistleblower lawsuit filed in 2012 by two officers who claim a code of silence permeates the department to the point that they were retaliated against for helping the FBI investigate two other cops who were eventually convicted of stealing money from drug dealers.

The Justice Department appears to be interested in that subject, too. Their requests include “a description of procedures or channels for employees to report or address alleged misconduct by other CPD employees” and “policies and procedures related to preventing or addressing retaliation against employees who report alleged misconduct by other CPD employees.”

Among other requests the feds have made of City Hall:

• Lists of incidents in which police officers “used force” and there were “injuries to CPD employees and/or members of the public.”

• The names of and resumes of all “outside consultants and/or instructors” involved in officer training.

• ”Information identifying all CPD officers who have been or are on light duty, medical disability, extended sick leave, or for any other reason are not on active duty.”

• Documents on the department’s “pilot program for body-worn cameras.”

• Information on hiring, training and disciplinary procedures; use-of-force policies; dispatch and service-call records; mental-health crisis response practices; “officer wellness” issues, and policies concerning “video and audio recordings” of police activity, including dashcam recordings.

• “Policies concerning CPD officers’ use of their personal cell phone, camera, video- or audio-recording equipment in the performance of their duties.”

On Wednesday night, Adam Collins, an Emanuel administration spokesman, said in an email: “As we have said for months, we will continue to cooperate fully and work closely with the Department of Justice in their review and we believe their work will be an important part of rebuilding trust in our police department.”