LOUISVILLE, Kentucky (NYTIMES) - The Louisville police officer who fired the shot that killed Breonna Taylor, a Black emergency room technician whose death set off a wave of protests on American streets, was told Tuesday (Dec 29) that the department was moving to oust him from the force, as was a second officer who arranged the poorly planned nighttime raid on her home.

The move is the most significant acknowledgement by the department that its officers had committed serious violations when they burst through Taylor's door late one night in March, encountered gunfire, and then fired a volley of shots at her and her boyfriend.

The terminations mark an effort by the city's interim police chief, Yvette Gentry, to achieve the reckoning she promised when she agreed to come out of retirement to lead the troubled department into the beginning of the new year.

Lawyers for Detective Myles Cosgrove, one of the officers who shot Taylor, and Detective Joshua Jaynes, who prepared the search warrant for the raid, said each had received notices of termination. Both have been on administrative reassignment as the investigations have been underway.

Until now, the only officer held accountable in the case had been Brett Hankison, a detective, who was fired in June for violating the department's deadly force policy by shooting off 10 rounds from outside the apartment through two of Taylor's windows.

He was indicted by a grand jury in September on three counts of wanton endangerment because shots he fired entered a neighbouring apartment.

The killing of Taylor, which rose to national attention around the time of the police killing of George Floyd in Minneapolis in May, helped fuel protests from Portland, Oregon, to New York that called on cities to divert money from their police departments.

Each development in the case seemed to bring more outrage, from the fact that none of the officers had been wearing body cameras to the announcement in September that only Hankison - and neither of the two officers who shot her - would be charged.

The anger persisted even after the protests over Floyd's death subsided, as protesters asked who was safe from the police if officers could kill a promising young woman in her own home and remain on the payroll.

As the months dragged on, the city's inaction came to be seen by many in Louisville as representative of a culture of impunity, and a message that there were few consequences for police officers who killed Black residents.

Mayor Greg Fischer, a Democrat, resisted calls to fire the previous police chief until June, when a popular restaurant owner was shot and killed as police officers and National Guardsmen attempted to disperse public demonstrations over Taylor's death.

But when Gentry, who retired in 2015, took over as interim chief, she promised a different approach.

"She did the heavy lifting that many men before her - many chiefs - have been unable to do," said Jessica Green, the chairman of the City Council's public safety committee. She said she expected that more officers would be disciplined.

Gentry, who is Black, has been clear that she is not interested in a permanent appointment, and her time as interim chief is soon coming to a close. Fischer is expected to announce a permanent chief early in 2021, but he has kept the search under wraps.

Whoever takes the job will face a mountainous challenge. When the city asked residents what qualities they wanted from a police chief, nearly a quarter of respondents urged the city to "defund the police."

Taylor's family and activists have been clear in their demands for criminal charges, which now rest with the FBI, whose agents are reviewing the case for possible federal crimes, such as civil rights violations.

The Justice Department, which oversees the FBI, has scaled back its oversight of local police forces under President Donald Trump, and on Tuesday, the department announced it was not bringing any charges after a years-long investigation into the police killing of Tamir Rice, a 12-year-old Black boy in Cleveland who was shot while holding a pellet gun.

President-elect Joe Biden has condemned Taylor's killing but said little about the decision not to file charges against any other officers.

The March 13 raid, in which Louisville officers were searching for evidence in a drug case, was compromised by poor planning and reckless execution, a New York Times review of witness accounts, video footage and officer statements showed. For nearly 30 minutes after Taylor was shot, she received no medical care.

Police officers said they knocked loudly on her door and repeatedly announced themselves, though most of the neighbours said they did not hear them do so. Taylor's boyfriend, Kenneth Walker, said he and Taylor had been in her bedroom and were terrified by the noise; after the officers knocked the door off its hinges and entered the apartment, Walker fired a shot toward the door, striking one of the officers in the leg.

Cosgrove, a 15-year veteran of the department, shot Taylor at least three times, killing her, according to an FBI ballistics analysis. He was the second person to enter Taylor's apartment and fired 16 rounds down the hallway, according to the analysis.

Jaynes, who did not take part in the raid, had been assigned to a unit formed shortly before the operation that was designed to focus on micro-locations plagued by violent crime.

After analysing crime statistics, the unit focused its attention on a street of derelict and abandoned houses in West Louisville, where Taylor's former boyfriend was suspected of operating a series of trap houses.

At issue in the accusations against Jaynes is the search warrant affidavit for Taylor's apartment that asserted that the police had spoken with the US Postal Service and verified that parcels intended for Taylor's ex-boyfriend had been delivered to her apartment. Gentry said Jaynes had been misleading because he had actually gotten the information not from the Postal Service, but from another police officer.

"Having an independent, third party verify information is powerful and compelling information," Gentry wrote in the letter to Jaynes. "The inclusion of this in the affidavit as a direct verification was deceptive."

Thomas Clay, the detective's lawyer, said his client had never lied in getting the search warrant to search Taylor's apartment.

"They have basically tried to throw him under the bus and he's not going to fit under the bus because he did nothing wrong," Clay said. Jaynes will have an opportunity to respond to the chief's claims at a department hearing on Thursday, according to the letter.

A lawyer for Cosgrove, Jarrod Beck, declined to comment beyond confirming that his client had also received a termination letter.

Taylor's family claimed that no drugs or proceeds of drug trafficking were found at her apartment. The police department counters that it never conducted a full search, calling it off once the shooting occurred. In a series of recorded jailhouse calls in the hours after her death, Taylor's ex-boyfriend told another woman that he had left thousands of dollars with Taylor.

Grand jurors declined to pursue charges against Cosgrove or Sgt Jonathan Mattingly, the officer shot in the leg who also shot Taylor. Their decision led to raucous protests in which two Louisville police officers were shot.

Several grand jurors have since said that prosecutors did not ask them to consider homicide charges, and protesters have expressed anger at Daniel Cameron, the Republican attorney-general who oversaw the proceedings. But legal analysts have said that the officers could be seen to have been acting in self-defence because Walker fired the first shot.

After the raid, Louisville officials banned the use of no-knock warrants, which allow the police to forcibly enter people's homes to search them without warning. In the raid of Taylor's apartment, officers had received court approval for a no-knock entry, but the orders were changed before the operation to require them to identify themselves.

Taylor's family and supporters have called for punishment and criminal charges against all the officers who had a hand in her death. In September, Louisville officials agreed to pay US$12 million (S$15.9 million) and institute reforms in order to settle a wrongful-death lawsuit filed by Taylor's mother, Tamika Palmer.

Gentry's move to terminate the officers was celebrated by many activists on Tuesday, even as they said that more reforms must follow.

"There was really no way for our community to begin to heal without something being done with the officers involved," said Sadiqa Reynolds, who leads the Louisville Urban League, adding, "It takes courage to come in behind these white men who said they couldn't do anything and to do something."