(CNN) The abrupt end to Eddie Johnson's time atop the Chicago Police Department caps what has been a tumultuous few years for the force.
Johnson announced his impending retirement last month after serving three decades on the force and spending more than three years as police superintendent.
Despite that plan, Mayor Lori Lightfoot fired him on Monday, saying that he had lied about an October incident in which he was found asleep in his car. She called his actions "intolerable."
Here's a look at some of the biggest events of his time leading the Chicago police, including the Laquan McDonald trial, Jussie Smollett's police report and the ongoing persistence of gun violence.
Johnson was appointed superintendent in 2016 by then-Mayor Rahm Emanuel months after video was released of the October 2014 police shooting of Laquan McDonald. Johnson had been the chief of patrol prior to his promotion.
The McDonald video, which showed an officer shooting the teenager 16 times, sparked widespread protests against the police treatment of African Americans and the city's attempts to keep the video secret. The shooting also prompted the Justice Department in 2015 to launch an investigation into the Chicago Police Department and led to a consent decree creating a series of reforms.
An investigative report from Inspector General Joseph Ferguson revealed the extent of what his office described as an elaborate cover-up by 16 officers and supervisors.
Officer Jason Van Dyke was found guilty of second-degree murder last year and sentenced to nearly seven years in prison. Three other Chicago police officers were found not guilty of covering up details in McDonald's death.
After becoming chief, Johnson moved to fire five officers involved in McDonald's shooting. He also announced several changes to how Chicago police defines and trains officers on the use of force.
Chicago has often been singled out for its disturbing gun violence, but the city has actually seen a broad decline in violent crime over the past few decades.
Violent crime rates peaked in American cities in the 1990s and have been steadily decreasing ever since, according to the Congressional Research Service. The violent crime and homicide rates increased from 2014 to 2015 and from 2015 to 2016, but both rates remain near historical lows and have decreased in the years since.
Chicago has closely followed those national trends. Homicides spiked in Chicago in 2016, topping 700 for the first time in decades.
But since then, the numbers have declined year over year.
Police said in October that the number of murders and shootings was down more than 10% for the year compared to the same period in 2018. Through September of this year, there have been 1,633 shootings, according to statistics from the Chicago Police Department. In the same time period last year, there were 1,836 shootings recorded.
During Johnson's retirement speech last month, he said that reducing gun violence was "one of the greatest accomplishments of my career."
Given that backdrop of Johnson's focus on making Chicago safer, the saga of "Empire" actor Jussie Smollett became personal for him.
Smollett, who is gay and black, told authorities he was attacked early January 29 by two men who were "yelling out racial and homophobic slurs" and "poured an unknown chemical substance" on him, according to police. He also said one of the attackers put a rope around his neck, which a police spokesman said was shaped like a noose.
Chicago police began investigating the case but could not corroborate his claims. Instead, police say Smollett paid two brothers $3,500 to stage an attack on him in an attempt to bolster his fame. Smollett has maintained that he was telling the truth in his report.
Smollett was charged with 16 counts of disorderly conduct for what police said was a false police report, but the Cook County State's Attorney's office dropped all of the counts. A special prosecutor has been appointed to examine the handling of the case.
Johnson took a particular personal interest in the case and said that police were "pissed off" about the alleged hoax. He told CNN he did not want "manufactured things" to stop what he said was a positive trend on making Chicago safer.
"We've made a lot of progress in the past three years," Johnson told CNN. "Crime is down, we have built up and repaired relationships in the black communities, the black and brown communities. So we don't want to lose that momentum."
"I don't want anything to disrupt that (progress) unless it's earned," he added. "I just don't understand the nature of something like this because it could really cause an issue in this city."
Lightfoot said she fired Johnson because of his actions related to the nights of October 16 into October 17.
A police statement said that Johnson was driving home early on the 17th when he felt lightheaded and parked his car near his home. Officers found him after a passerby called 911 to report that a person was asleep at a stop sign. He was not administered a sobriety test.
Speaking to reporters afterward, Johnson said that he felt like his blood pressure was rising when he decided to park his car. He said he had been prescribed a medication after he suffered a blood clot in the summer. He said he thought he felt ill because his doctor had changed his medication earlier in the week, but he accidentally missed taking it.
He also told Lightfoot that he "had a couple of drinks with dinner," and he called for an internal investigation into the incident.
But on Monday, Lightfoot fired Johnson and said his actions were "intolerable for any leader in a position of trust."
"Mr. Johnson failed the hardworking members of the Chicago Police Department, he intentionally misled the people of Chicago and he intentionally misled me. None of that is acceptable," she said.
She said his actions demonstrated "a series of ethical lapses and flawed decision making," and added that he was dishonest with the public in his news conference afterward.
"He was not caught off guard and he had plenty of time to choose his words, and the choice he made was a communicated narrative replete with false statements all seemingly intended to hide the true nature of his conduct the evening before," the mayor said.
She declined to comment on the case's specifics, out of deference to Johnson's family and respect for the inspector general's ongoing investigation, she said. The inspector general's report may be made public later, she said.