They were neighbors who didn't know each other, lived one floor apart in the same Dallas apartment complex and were devoted to their careers.

Amber Guyger had been on the city's police force for four years, starting on patrol and assigned to an elite crime response team that makes high-risk arrests.

Botham Jean, a 26-year-old accountant and native of the island nation of St. Lucia, went by Bo and called Texas home after he was hired by a prestigious firm.

On Sept. 6, 2018, just before 10 p.m., their names would become inextricably linked when Guyger, who was off duty but in uniform, entered Jean's apartment and fatally shot him. She later told investigators that she had confused his unit for hers and mistook him for a burglar after she saw a "large silhouette" in the darkness.

Jean's death led to protests, Guyger's firing and a grand jury indictment for murder. It also reignited conversations about racial bias, police use of force and concerns that law-abiding citizens are not safe even in their own homes.

Now, more than a year after the shooting, opening statements in the trial against Guyger, 31, are due Monday under a cloud of unanswered questions and the weight of a community being asked to put its faith in the court system.

"I think a lot of jurors do tend to give the benefit of the doubt to police. But is the jury going to accept that she made a reasonable mistake?" Kenneth Williams, a criminal law professor at South Texas College of Law in Houston, asked. "If there is an acquittal, I think there will be a lot of outrage in the community. There will be a feeling like the police will get away with anything — even against a person sitting in his own apartment, obeying the law."

A 'mistake of fact' defense

Attorneys in the case have been unable to speak publicly after state District Judge Tammy Kemp issued a gag order in January.

The prosecution may focus on Guyger's mental state on the night of the shooting and that she had the ability to prevent the deadly chain of events, said Amber Baylor, an associate professor and director of the Criminal Defense Clinic at the Texas A&M School of Law.

"A self-defense claim also centers on how a reasonable person would have acted — and the prosecution will want to distinguish Guyger's reaction from that of a reasonable person in her shoes," Baylor said.

While it is unclear what arguments Guyger's defense team will lay out, legal experts say its case will likely hinge on convincing the jury that Jean's death was a mistake with no criminal intent behind it.

Williams said the use of a "mistake of fact" defense under Texas law is not uncommon, and it will require a jury to parse out the evidence and testimony to determine if Guyger made a reasonable error when she believed she was killing an intruder in her own home and exercising her right of self-defense.

Alex Piquero, a criminologist at the University of Texas at Dallas, said the prosecution may likely argue that she had to have known where she was and that she should be held accountable and punished accordingly. The judge may instruct jurors to consider murder, which carries a maximum sentence of life in prison, or a lesser charge.

"Of course, all anyone knows is what has been reported in the press, so it is unknown and unclear not only what each counsel has to martial their argument about Guyger's guilt, but most importantly, how 12 jurors will interpret that evidence, form their view about what happened during the tragic event, and then whether they can agree on specific charges," Piquero said.

Revelations at trial

Court documents and arrest warrants have given some indication as to what propelled Guyger to pull the trigger.

Guyger had driven home to the South Side Flats complex after a long shift and parked on the wrong level of the garage, getting off on the fourth floor instead of the third.

When she arrived at what she thought was her apartment, she said, she tried to insert her electronic key fob, but the door pushed open. She walked into the darkened unit and encountered Jean, drawing her weapon and firing twice, the arrest affidavit said.

Botham Jean Harding University

Guyger told investigators that the person "did not follow" her verbal commands before she opened fire with her service weapon.

Some of the holes in the case should be filled in during the trial, legal observers say, including what Guyger may have instructed Jean and exactly how many hours her shift had lasted. Reports vary on whether she was working a shift that was as long as 12 or 15 hours.

It's also unclear what Guyger might have done between leaving work and going home, and blood and alcohol tests taken from her the night of the shooting could be submitted into evidence.

Baylor said Guyger's experience in law enforcement is open to examination, but it will be up to the judge to decide what evidence or contextual information about her job will be admissible at trial.

"It's true that defense teams have used officers' work experience to justify making quick decisions in potentially dangerous or volatile situations," Baylor said. "One could also argue that an officer is trained to assess the situation more carefully than a civilian, and de-escalate volatile situations."

Also unanswered is how exactly Guyger would have mistaken Jean's apartment, which was directly above hers, and gained access inside. According to reports, Jean's unit had a red floor mat outside the front door. And while Guyger said she was able to push open the door, an attorney representing the Jean family in a federal civil lawsuit said earlier this year that two independent witnesses claimed that before the shooting, they heard knocking coming from the hallway.

Crime scene reconstruction experts and forensic video analysts are expected to be called as witnesses for the state.

Whether Guyger takes the stand in her own defense is still uncertain, and legal experts say such a tactic can backfire. Last year, white suburban Dallas police officer Roy Oliver testified in his trial in the fatal shooting of black teenager Jordan Edwards, and was subsequently sentenced to 15 years in prison for murder.

"It is certainly a risky move because there is always the possibility that her testimony could undermine whatever benefit of the doubt that she might get from the jury," Williams said of Guyger.

Confronting racial bias

An attempt by defense lawyers to move the trial to another county outside of Dallas, where the demographics are whiter and more conservative, was rejected by Judge Kemp this month. Guyger's defense argued that the intense media attention would prevent her from getting a fair trial.

The racial makeup of the jury in Dallas County is unclear.

In pretrial hearings this year, Guyger has "softened" her appearance, legal observers say, ditching the pulled-back hairstyle and dark clothing more associated with law enforcement.

Amber Guyger arriving for jury selection. Potential jurors to face questions from attorneys and judge Tammy Kemp. Will soon get whittled down to 220. Need 12 and 4 alternates.



Guyger Murder Trial Jury Selection Continues, Change of Venue Still in Play https://t.co/rawgWETpDc pic.twitter.com/UV1yfE7PRJ — Larry Collins (@LarryNBC5) September 13, 2019

Meanwhile, how police have handled the case was initially scrutinized after complaints by social activist groups that it took three days before Guyger was arrested and that she was charged with manslaughter, although that was later revised to murder.

"There are organizations that have been invested in the city addressing race and policing concerns for years," Baylor said. "Last year's trial of Roy Oliver and the Guyger trial bring up the issues that these advocates have tried to highlight regarding race and police violence — albeit under tragic conditions."

Jean's death became a rallying cry in Dallas, and earlier this year, the city council unanimously voted to expand the powers of the city board that hears complaints about police misconduct and give a "monitor" the ability to review completed police investigations.

His name was also added to a growing list of incidents in which police were intervening in situations where black people were doing ordinary, nonthreatening activities, and as another extreme example of police opting for deadly force against a person of color.

In the aftermath, his family asked publicly if Guyger would have been so quick to shoot him if he were not black.

"While we may not know whether the defense or prosecution will speak on the implications of race explicitly," Baylor said, "it's safe to expect that internally, both the prosecution and defense teams will be considering jurors' lens on race and racism in crafting their strategies."

The case is also unfolding in a city that has seen its leadership and law enforcement become increasingly diverse. Dallas Mayor Eric Johnson, who took office in June, is black, as are Dallas Police Chief U. Renée Hall, Dallas County District Attorney John Creuzot and Dallas County Sheriff Marian Brown.

Kemp, who won re-election last year, is also black, and those who know her say she runs her courtroom with impartiality and will not tolerate the Guyger trial becoming a media circus.

"This is probably going to be the biggest case she's ever handled," said Anthony Eiland, a private attorney and former felony prosecutor with the Dallas County District Attorney's Office. "She's going to bend over backwards to make sure everything's being done right."