A former Fort Worth police officer, Aaron Dean, was convicted of manslaughter in the shooting of Atatiana Jefferson. She was shot through her bedroom window.SAN ANTONIO — A white police officer who shot and killed a Black woman when he fired a bullet through her bedroom window while responding to a call from a concerned neighbor was found guilty of manslaughter by a jury in Texas on Thursday.The jury in Fort Worth did not convict the officer, Aaron Dean, on the murder charge that prosecutors had sought. He could face up to 20 years in prison after the two-week trial that took place after years in delays.The October 2019 shooting occurred when Atatiana Jefferson, who had been playing video games with her 8-year-old nephew, heard a noise and grabbed her gun as she went to look out her bedroom window. Mr. Dean, who had been called by a neighbor who had reported open doors at the house late at night, yelled at Ms. Jefferson to put her arms up and immediately fired a single shot through her window.Atatiana Jefferson.Jefferson Family, via Associated Press“She started crying,” Ms. Jefferson’s nephew, Zion Carr, told the jury in testimony last week. He said his aunt collapse near the window, moaning in pain, before she died. “I was thinking, is it a dream?”The shooting came long before two higher-profile cases, the deaths of Breonna Taylor in Louisville, Ky., and George Floyd in Minneapolis at the hands of white police officers, that together sparked a national reckoning over race and policing. But Ms. Jefferson’s death in Fort Worth brought to the surface a longstanding mistrust of the police in Black and Latino neighborhoods there and elsewhere in Texas.Vigils turned into street protests and at times led to tense confrontations between residents and local elected officials. Initially, Fort Worth authorities responded to the public outrage by acting swiftly. The Fort Worth Police Department released the officer’s body-worn camera and arrested Mr. Dean days later.But even as the officers in the cases of Mr. Floyd and Ms. Taylor were tried in court, the trial in Fort Worth remained in limbo for years after a series of delays caused by the coronavirus pandemic, personal tragedies and legal maneuvers by the defense.After two years of legal back-and-forth, defense lawyers argued in legal filings that the judge assigned to the case, David Hagerman, had shown bias against their team and treated them with anger and hostility. The judge was removed from the case over the summer.The trial had suffered another delay when it was announced that the lead defense counsel, Jim Lane, was diagnosed with a terminal illness. Mr. Lane died one day before jury selection was set to begin in late November.The trial finally began on Dec. 6 with a new judge, George Gallagher, and 14 jurors, none of whom are Black.A memorial in the front of Ms. Jefferson’s home in 2019.Tom Fox/The Dallas Morning News, via Associated PressDuring the course of the trial, prosecutors argued that Mr. Dean acted recklessly and used excessive force during a routine call where no one appeared to be in imminent danger. “This is not a self-defense case. This is murder,” Ashlea Deener, the assistant district attorney, told the jury.Miles Brissette, representing the officer, said his client was not to able to discern Ms. Jefferson’s gender or race from where he stood outside her window and that he acted in self-defense only after he noticed a person holding a gun with a “a green laser mounted on it pointing directly at him.”“This is a tragic accident,” Mr. Brissette said.Mr. Dean testified in his own defense and at one point admitted that the way he responded to the call “could’ve been better.” But he emphasized that he was trained to “stop the threat.”At the time of the incident, the union that represented Mr. Dean, the Fort Worth Police Officers Association, said that he had never been the subject of an investigation and was “very shaken up” by the shooting. The only notable entry in his personnel file was for a traffic accident, the union said. He joined the department in April 2018, one month after completing his classes at the police academy.Ms. Jefferson’s young nephew was the first witness to take the stand.He recalled moving in not long before the shooting with his grandmother and his Aunt Tay, as he called her, because his mother was ill and could not care for him. His aunt, who graduated in 2014 from Xavier University of Louisiana with a degree in biology and sold medical pharmaceutical equipment, dreamed of going to medical school. But she also had a playful side and loved playing video games with him, the boy told the jury.On the night of Oct. 12, 2019, the two burned some of the hamburgers they were cooking and opened two doors to let the smoke out, Zion said during his testimony.Zion had gone to bed and his aunt had stayed up playing video games when a neighbor noticed that the doors were open at around 2:30 a.m. and called a nonemergency number to report it, according to a summary of the events by the prosecution.Mr. Dean and his partner, Carol Darch, who at the time were recent graduates of the police academy, responded to the call for an “open structure,” a vague classification that could mean anything from a burglary in progress to a report of an abandoned dwelling. It was not a welfare check, prosecutors said, in which case officers would often knock on the house doors or call inside.Mr. Dean and his partner, Carol Darch, right, responded to the call for an “open structure,” a vague classification, prosecutors said.Pool photo by Amanda MccoyBy that point, Zion recalled in his testimony, he had woken up and joined his aunt in playing video games. That is when, he said, Ms. Jefferson heard a strange noise coming from outside and reached for a gun she kept in her purse.Ms. Deener, the prosecutor, said Mr. Dean yelled, “Put your hands up! Show me your hands!” but never gave Ms. Jefferson a chance to react.Zion said he did not remember what led to the shooting, only that one minute his aunt was standing by the window and the next she was on the floor.“She was crying and just shaking,” he said.The day after he testified, the jury saw a video interview recorded two hours after the incident in which the boy, still wearing his pajamas, provided more details. He is heard telling a woman that he saw his aunt point her weapon toward the window and that he managed to see an officer’s badge, flashlight and gun on the other side of the window. The jury also heard him in the same video say that he heard the officer scream and demand that his aunt put her hands up; he said the officer fired his gun after she failed to follow his commands.The night of the incident, he said, he had been confused, unsure if what he had seen was real or part of a dream. He learned she had died days later.