By Bill Ruthhart and Hal Dardick

Mayor Rahm Emanuel on Tuesday announced he has dismissed Chicago police Superintendent Garry McCarthy, citing a lack of public trust in the police leadership in the wake of the high-profile shooting that eventually led to a white officer being charged with first-degree murder in the death of a black teen shot 16 times in a Southwest Side street last year.

Emanuel said he and McCarthy began discussing the future of the police department on Sunday. "This morning, I formally asked for his resignation," Emanuel said at a City Hall news conference where he appointed a task force to look at police accountability.

The mayor said it's an "undeniable fact" that public trust has eroded in the Chicago Police Department.

As late as 8 a.m. Tuesday, McCarthy was on the radio talking about the Laquan McDonald shooting and praising the mayor's task force plan.

"How am I? I'm a little busy and a little bit stressed out, but staying the course," McCarthy said when asked how he was doing by WGN-AM 720's Steve Cochran.

The mayor, however, is changing course after his office issued statements of support for McCarthy during the past week.

For 4 years, Emanuel had stood by McCarthy through various rocky patches, including a major spike in homicides and a number of high-profile murders and shootings of young children caught in the gang gunfire of Chicago's most violent neighborhoods. Then came the intense criticism of how the two handled the police shooting of 17-year-old McDonald. After Cook County prosecutors charged Officer Jason Van Dyke with first-degree murder a week ago, federal prosecutors disclosed that their probe of the fatal shooting, which was announced in April, remains "active and ongoing."

Van Dyke shot McDonald in October 2014. For much of the last year, Emanuel and his lawyers fought in court to keep a police dashboard camera of the shooting under wraps, arguing that releasing it publicly could interfere with a state's attorney and federal investigations into the shooting.

But when a Cook County judge's ruling forced Emanuel to release the video to the public last week, the fallout for McCarthy and Emanuel was sharp and immediate. Protesters took the streets and blocked entry to Magnificent Mile stores on one of the busiest shopping days of the year on Friday. Black aldermen called for McCarthy to be fired. Cook County Board President Toni Preckwinkle urged Emanuel to do the same. Some Latino aldermen followed suit, as did newspaper editorial writers, television commentators, columnists and activists from around the country.

The more-than-weeklong protests and public backlash -- both in Chicago and across the country -- contributed to McCarthy's ouster.

With it comes the departure of Emanuel's only police superintendent since he took office in May 2011. McCarthy's tour atop the department was longer than typical for the pressure-cooker job of running one of the nation's largest, and most controversial, police departments.

In hiring McCarthy, Emanuel sought a credible voice, a superintendent who came to Chicago after stints as a top commander in New York City and as the chief in Newark, N.J., where he built a career on using a combination of cutting edge statistical trends and intelligence to knock back violent crime. Never hesitant to talk tough about gangs or guns in front of a microphone, McCarthy was the face of the police department, often taking pressure off the mayor to address crime issues.

But the McDonald shooting exposed a perceived weakness -- that Emanuel and McCarthy had not done enough to institute meaningful reforms in a police department long known for a culture of corruption, torture, wrongful convictions and lax discipline.

As the mayor and McCarthy both prepared for the fallout of hundreds of thousands of people watching the video of Van Dyke repeatedly shooting McDonald, both sought to portray the incident as the case of a bad apple that did not reflect more systemic problems in the department.

But for many Chicagoans, the story of McDonald's death held an all-too-familiar set of circumstances: City Hall initially casts the incident as an act of police self-defense only for the facts to bear out a different story later.

Immediately after the shooting last October, a Chicago police union spokesman said that McDonald had lunged at officers before he was killed. And in an official statement the next day, Chicago police said McDonald "refused to comply with orders to drop the knife and continued to approach the officers." The video, however, showed McDonald walking down the street, away from officers as Van Dyke opened fire.

With that video airing on news telecasts across the country and online around the world, McCarthy and Emanuel's one-bad-apple narrative of Van Dyke's actions didn't square with Chicago's sordid police history that once again was back in the national spotlight. Serving as the backdrop: decades' worth of police torture and wrongful conviction cases, corruption and ineffectual oversight in shootings and other excessive force actions. Time and again, the department had quickly cleared officers of allegations, only to have civil litigation later reveal video and other evidence that painted a much darker picture of police misconduct.

It took Emanuel more than a week after Van Dyke was charged with murder to publicly address the notion, appointing a task force to make recommendations to approve police accountability. It was the type of announcement many politicians make when faced with a crisis to buy time and create breathing room.

But it wasn't enough to spare McCarthy from losing his job.

McCarthy's familiar New York accent, flat top hair cut and thick mustache quickly made him well-known in the city, particularly after he spearheaded City Hall's response to the 2012 NATO summit that brought scores of international leaders, and days of large-scale protests, to Chicago.

As protesters had violent clashes with police in the streets, McCarthy could be seen, standing at the back of the line in his white shirt and blue cap running the show. At the time, McCarthy had struggled with criticism from within the department that he'd brought an arrogant New York-knows-best attitude and was too cozy with Emanuel, but his decision to be visible on the ground helped his standing with the rank-and-file.

"It's where I'm supposed to be," McCarthy said at the time. "And I have great reverence for officers. I interact with them very easily. You can't fake it. You either are or you aren't. I'm very comfortable in that role."

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