CHICAGO (CBS) — Jury selection is underway in what will be one of the most watched trials in America, as Chicago Police Officer Jason Van Dyke faces murder charges in the 2014 shooting death of Laquan McDonald.

Van Dyke quietly slipped into the Leighton Criminal Court Building early Wednesday, ahead of the painstaking process of trying to pick a jury to decide his fate.

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Later, protesters from more than half a dozen activist groups gathered outside the courthouse at 26th and California to make their voices heard as the trial begins.

Potential jurors walked in through temporary fencing set up ahead of the historic murder trial. Around 11:30 a.m., the first set of potential jurors was brought into Judge Vincent Gaughan’s courtroom to begin the selection process.

Jury selection in Van Dyke’s trial comes one day after Mayor Rahm Emanuel announced he wouldn’t be running for re-election. Emanuel had been widely criticized for his handling of the McDonald case, accused by some of keeping dashboard camera video of the shooting under wraps until after the 2015 election.

Van Dyke was charged with McDonald’s murder the same day the video was released in 2015. Jury selection in his trial likely will take several days. Potential jurors will start by picking up and filling out questionnaires meant to gauge whether they have any preconceived notions about the high-profile case.

Exactly what the jury pool will be asked about the case, including the video of McDonald’s death, is unclear, because the questionnaire remains under seal.

Judge Gaughan didn’t want the questionnaire made public, because he believes keeping its contents private will result in more honest answers from potential jurors.

As the day’s proceedings began, protesters assembled across from the courthouse, chanting slogans like, “We want freedom, freedom; all these racist cops, we don’t need ’em, need ’em!”

Van Dyke’s defense attorneys have been seeking a change of venue for the trial, arguing the veteran officer can’t get a fair jury in Cook County, due to the extensive media coverage of the case.

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Gaughan has delayed ruling on that request until after jury selection has begun, holding out hope an unbiased jury can be seated in Cook County. Van Dyke still has the option of asking for a bench trial, meaning Gaughan would decide the verdict.

Van Dyke is the first Chicago police officer in decades to be charged with first-degree murder for an on-duty shooting. He shot McDonald 16 times on the night of Oct. 20, 2014, as police were responding to reports the teen was slashing tires near 41st and Pulaski.

McDonald was armed with a knife and allegedly had slashed the tire of a police car before Van Dyke arrived on the scene. In a report he filed after the shooting, According to the official police report of the shooting, McDonald attacked Van Dyke, and swung the knife in an “aggressive manner.”

However, dashboard camera video released the day Van Dyke was charged with murder contradicts the police account, and shows McDonald walking away from Van Dyke when he was shot.

At a news conference after Van Dyke’s final pretrial status hearing on Tuesday, McDonald’s relatives asked for the public to remain calm before, during, and after the trial. The family said they don’t want to see protests, regardless of the outcome.

“We’re asking for complete peace,” said McDonald’s great uncle, Marvin Hunter. “I’m concerned about riots and violence.”

Hunter said he believes Emanuel initially covered up the circumstances of the shooting, and his decision not to seek a third term is directly related to his handling of the McDonald case.

“It came from covering up the crime of Laquan McDonald as well, and so sometimes the coverup dictates the outcome. That’s the best way I can answer that,” he said.

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A source close to the mayor said Emanuel had been thinking about stepping down for a long time, and always thought he would serve only two terms.