Updated 11/24/15 – 9:49 p.m.

CHICAGO (CBS) — A Chicago police officer has been ordered held without bail, charged with first-degree murder in the shooting death of 17-year-old Laquan McDonald.

Cook County Judge Donald Panarese Jr. said he would not allow Officer Jason Van Dyke held to go free on bond until he’s seen dashboard camera video of the shooting. He scheduled another hearing for Van Dyke for Monday, and said prosecutors should have the video in court at that time.

In a statement Tuesday afternoon, McDonald’s family thanked supporters for their “outpouring of love and support for Laquan,” and asked for peaceful demonstrations once video of the shooting is made public.

“This is a difficult time for us. As we have said in the past, while we would prefer that the video not be released we understand that a court has ordered otherwise. We ask for calm in Chicago. No one understands the anger more than us but if you choose to speak out, we urge you to be peaceful. Don’t resort to violence in Laquan’s name. Let his legacy be better than that.”

Prosecutors said Van Dyke shot McDonald 16 times in a span of less than seconds on Oct. 20, 2014. McDonald was carrying a 3-inch blade, and was walking away from Van Dyke when the officer opened fire, according to prosecutors.

Cook County State’s Attorney Anita Alvarez said Van Dyke’s partner noticed the officer preparing to reload his gun after shooting McDonald, and heard McDonald struggling to breathe as he laid on the ground, so he told Van Dyke to hold his fire so he could kick McDonald’s knife away.

Alvarez said Van Dyke was on the scene less than 30 seconds before he started shooting, and had been outside of his squad car less than six seconds before he fired the first shot.

She said she has seen the video of the shooting several times.

“It is graphic, it is violent, it is chilling,” she said. “To watch a 17-year-old young man die in such a violent manner is deeply disturbing, and I have absolutely no doubt that this video will tear at the hearts of all Chicagoans.”

Van Dyke, a 14-year veteran of the force, was one of eight officers responding to calls of a suspected thief armed with a knife, but no other officer saw a need to use force that night, prosecutors said.

Alvarez said there also were several civilians who witnessed the shooting, including a motorist stopped on Pulaski Road, who said it appeared McDonald was trying to get away from police at the time.

“The motorist stated that McDonald never moved toward, launched at, or did anything threatening towards the officers before he was shot, and fell to the ground,” Alvarez said. “This witness stated that he heard a pause in the shots after McDonald fell to the ground, but then heard more shots. He also said that he did not see McDonald do anything threatening while lying on the ground that would cause the officer to continue to shoot.”

Alvarez said, based on the witness statements and other evidence, she determined the shooting was not a justified use of deadly force by Van Dyke.

“Clearly, this officer went overboard, and he abused his authority, and I don’t believe the force was necessary,” she said.

Asked why it took more than a year from when McDonald was killed to bring criminal charges, Alvarez said investigating a police shooting is a more complicated matter than investigating a case of one civilian shooting another. Alvarez said investigators and prosecutors must know how the officer was trained in the use of force, the department’s rules and regulations for the use of force, and the perspective of the officer at the time of the shooting.

“At the end of the day, I’d rather take my time and get it right, than rush to judgment and get it wrong. Rushing to judgment simply has no place in a professional investigation of this magnitude, and could only serve to jeopardize justice being done,” Alvarez said.

She also said her office was working in coordination with the FBI and federal prosecutors, and originally planned to wait until all sides had completed their investigation before announcing any charges, but after a civil court judge ordered video of the shooting be released to the public, she wanted to announce charges to provide context for the video.

Van Dyke arrived at the courthouse to turn himself in around 7:30 a.m. Tuesday, and was later formally charged with first-degree murder.

After the bond hearing, Van Dyke’s attorney, Dan Herbert, said the officer would be vindicated in court.

“We will be successful on this case. This is not a murder case, despite what you heard in the courtroom. It’s truly not a murder case, and we feel that we’re going to be very successful in defending this case,” he said. “This is a case that can’t be tried in the streets. It can’t be tried in the media. It can’t be tried on Facebook.”

The city’s police union has said McDonald was armed with a knife, was high on PCP, ignored police orders to drop his weapon, and eventually lunged at officers in the 4100 block of South Pulaski Road. Van Dyke’s attorney has said the officer opened fire in fear for his life.

McDonald family attorneys have said dashboard camera video of the shooting contradicts the police union’s version of events, and shows a brutal “execution.” They have said the video proves McDonald did not lunge at police, and was walking away when he was shot.

(Supplied Photo)

(Supplied Photo)

(Credit: CBS)

(Credit: CBS)

A Cook County judge has ordered the city to release that video by Wednesday and city officials released it Tuesday afternoon.

At a police recruit graduation ceremony Tuesday, Police Supt. Garry McCarthy said the department is prepared for protests and other demonstrations in the wake of the charges against Van Dyke. Detectives will be in uniform to help on the street.

“My mantra is going to be the same one that it always is, which is really simple. We’re going to facilitate and protect people’s First Amendment right to free speech, and we’re going to be intolerant of criminal behavior, and I have a very high regard for the community to support them,” he said. “We’ve had a lot of conversations regarding this. We do know that there are other people from other parts of the country who may want to cause problems, and we accept that.”

People who have seen the video have said it shows McDonald walking away from police when Van Dyke opened fire. The video reportedly shows Van Dyke firing the final two shots as McDonald was lying on the ground.

Mayor Rahm Emanuel released a statement saying, “Jason Van Dyke’s actions violated those standards and also the moral standards that bind our community together. Rather than uphold the law, he took the law into his own hands and it’s now up to the justice system to hold him accountable. But his actions are in no way a reflection of the dedication and professionalism that our police officers exemplify every day and that our residents expect throughout our city.”

Ministers who huddled with Mayor Emanuel on Monday at City Hall said they hope the charges against Van Dyke will defuse the tension ahead of the video’s release, but they weren’t making any guarantees.

“He [the mayor] definitely understands that we’re in a situation that has the potential to be a bombshell,” Rev. Corey Brooks said.

Rev. Ira Acree said many people in his community “feel betrayed.”

“Many are so very angry, and protests are imminent,” he said.

In a conference call with key civic leaders on Monday, Emanuel also urged calm once the video is released. He called the shooting of McDonald “hideous.” The mayor said he has not watched the video of the shooting.

At a news conference later on Monday, the mayor said: “You have a right to voice your opinions but do it in focused and responsible way so all voices heard.”

Although the mayor initially fought the effort to make the video public, he reversed course last week, and has since criticized the officer’s actions.

“This officer didn’t uphold the law. In my view, he took the law into his own hands; didn’t build the trust that we want to see, and he wasn’t about providing the safety and security. So, at every point, he violated what we entrust him,” he said Monday.

Attorneys for McDonald’s family have seen the video, and said it is shocking and disturbing, and have described the shooting as an “execution.”

“The first shot or two seem to spin him on the ground. He falls down. He’s down on the ground, and for the next 30 seconds or so, in this video, the officer just continues to shoot,” Neslund said earlier this month. “What you see are graphic puffs of smoke rising from Laquan and intermittently his body twitching, in reaction to the shots.”

The city’s police union has said McDonald was slashing tires with a 4-inch knife, and high on PCP, when he refused police orders to drop the weapon. Van Dyke has said McDonald lunged at him. His attorney, Dan Herbert has acknowledged video is graphic, but he said the officer feared for his safety, and the shooting was justified.

“He firmly believed he was in fear for his life and concerned about the life of his fellow officers,” Herbert said last week.

The city agreed to a $5 million settlement with McDonald’s family even before a lawsuit was filed. Van Dyke, a 14-year veteran, has been stripped of his police powers, pending investigations by federal and Cook County prosecutors.