CLEVELAND, Ohio -- The trial of Cleveland police officer Michael Brelo begins today. The 31-year-old is charged in the deaths of Timothy Russell and Malissa Williams following a police chase and shooting on Nov. 29, 2012.

A lot has been written and said about this case over the last two and a half years, including an investigation by the Bureau of Criminal Investigations. There was also a report from the Ohio Attorney General who deemed the chase and shooting the result of a "systemic failure in the Cleveland Police Department."

There have also been public comments from the prosecution, and a lot of pre-trial motions filed at Cuyahoga Common Pleas Court.

We've compiled answers to some frequently asked questions, basically everything you need to know, before the start of the trial. If you have any additional questions, please ask them in the comments below and we'll do our best to answer them.

What happened on Nov. 29, 2012?

Who is Michael Brelo?

What is he being accused of?

Why was he the only person charged with manslaughter?

What does Brelo have to say?

Why is a judge deciding this case?

Will prosecutors treat Cleveland police as "hostile witnesses?"

What can we expect during the trial?

What happened on Nov. 29, 2012?

What, exactly, happened on that November night is what prosecutors and defense attorneys have been trying to pin down for years. The Bureau of Criminal Investigations findings create a clearer picture of what likely transpired.

Timothy Russell and Malissa Williams were in a car together. Both were homeless and had met at a shelter where they were receiving free meals. People who knew them told investigators they were most likely out looking to buy drugs.

A plainclothes police officer spotted Russell's 1979 light blue Chevy Malibu by an area known as "the wall" on Lakeside Avenue known for drug deals. Shortly before 10:30 p.m. the officer called in the car's license plate. The plates came back clean, but the officer tried to pull Russell over for a turn signal violation. Russell instead sped away, and the police officer was unable to catch up.

At that point, Russell sped past two other officers outside the Justice Center on Lakeside. The officers heard a loud noise they believed was a gunshot from the speeding vehicle. Investigators later concluded the sound was most likely the Malibu backfiring. The police officers called in a report that someone shot at them from the speeding vehicle. This triggered the chase through Cleveland, onto the eastbound lane of Interstate 90 and into East Cleveland.

The chase reached speeds of 100 mph. Investigators found that at one point, there were 62 police cars involved in the chase, including officers from Cleveland, East Cleveland, Bratenahl, the Cuyahoga County Sheriff's department, the Ohio State Highway Patrol and RTA.

The chase ended when Russell turned into Heritage Middle School in East Cleveland. Police cars surrounded the Malibu. Several police officers reported seeing a gun in the car, and believed that Russell was trying to run them over. One officer began to shoot, and others opened fire. Many officers believed the suspects were firing out of the vehicle, but later investigations found no evidence of a weapon in the car.

In the end, 13 police officers shot 137 bullets at Russell and Williams. Russell was hit 23 times, and Williams was hit 24 times. Both were declared dead by 11:24 p.m.

Who is Michael Brelo?

Brelo, 31, had been with Cleveland police for about five years when the police chase and shooting happened. He remains on unpaid leave from the department while his case is pending.

Brelo served in the Marines from 2003-10 prior to joining the police force. He was deployed to Iraq in 2005, where he told investigators he never had to deploy his weapon in the line of duty.

What is he being accused of?

Brelo was indicted on two counts of voluntary manslaughter on May 30, 2014. He pleaded not guilty to both counts.

Five police supervisors were indicted at the same time for negligence of duty.

Why was he the only person charged with manslaughter?

Prosecutors have argued that although 13 police officers were involved in the shooting, only Brelo continued to shoot after other officers perceived any threat was over. Prosecutors have also pointed to the BCI investigation, which found that Brelo jumped on the back of a police car, and from there onto the hood of the Malibu and shot directly down at the victims.

What does Brelo have to say?

Brelo hasn't said much, and it's unclear if he'll take the stand. But he told BCI investigators he thought the Malibu would run them over, that he saw a gun in the vehicle, and he thought they were being shot at.

"I've never been so afraid in my life," Brelo said in his interview. "I thought my partner and I would be shot and that we were going to be killed."

Brelo also told investigators that he remembers jumping on the hood of a police car, and then he remembers standing next to the vehicle, but he doesn't remember what happened in between. He said he does not recall standing on the hood of the Malibu, nor does he recall how he got to the ground.

Why is a judge deciding this case?

Brelo waived his right to a jury trial last month. Prosecutors argued in a counter-motion that his decision was racially motivated, and that the black communities of Cleveland and East Cleveland have a right to hear the case. But Judge John P. O'Donnell ruled that he will be the one to hear the trial, as in Ohio the right to have or refuse a jury lies with the defendant alone.

Will prosecutors treat Cleveland police as hostile witnesses?

Prosecutor Timothy McGinty's office has filed a motion saying they would like to treat any Cleveland police officers that might testify as hostile witnesses. The motion argues police officers were not fully cooperative with the BCI investigation and with prosecutor's efforts leading up to the trial.

If the judge allows this to happen, the prosecution will be allowed to ask leading questions, which is not permitted in ordinary cases.

Steve Loomis, president of the Cleveland Police Patrolmen's Association union, was dismissive of the prosecution's request, saying officers have cooperated with the investigation up until this point, and will continue to do so.

What can we expect during the trial?

Prosecutors have said they plan to call about 50 witnesses, and the defense will call several expert witnesses of their own. Police officers involved in the chase and shooting will likely be asked to testify, as will medical examiners, ballistics experts, and audiologists.

The trial starts April 6. Judge O'Donnell has forbidden live streaming from the courtroom, but cleveland.com will have a live blog of the court proceedings and keep you up to date on everything that's happening.