LOUISVILLE — Buildings have been boarded up and highway access restricted in Kentucky's largest city as residents brace for a possible announcement from the state attorney general on whether charges will be filed against officers involved in the death of Breonna Taylor, the 26-year-old Black woman who has become an international symbol of the racial-justice movement.

Louisville Mayor Greg Fischer (D) declared a state of emergency Tuesday in anticipation of an announcement and "the potential for civil unrest." Law enforcement leaders have canceled days off for police, and officers were told to prepare to work 12-hour shifts.

Kentucky Attorney General Daniel Cameron (R) has given no public indication of when he will conclude his four-month investigation of the drug raid that led to the fatal shooting of Taylor in her apartment shortly after midnight March 13. "An investigation, if done properly, cannot follow a specific timeline," he said in a statement earlier this month.

One of the officers involved in the Taylor case, Sgt. Jonathan Mattingly, sparked more controversy in the city — which has experienced more than four months of protests — with an email to fellow officers Tuesday morning that characterized police as defenders of order against forces of evil.

“You DO NOT DESERVE to be in this position,” Mattingly told the officers. “The position that allows thugs to get in your face and yell, curse and degrade you. Throw bricks, bottles and urine on you and expect you to do nothing. It goes against EVERYTHING we were all taught in the academy.”

Kent Wicker, an attorney for Mattingly, confirmed his client sent the email, which was first reported by Vice News.

Louisville police killed Taylor while executing a “no knock” search warrant. They uncovered no illegal substances in her apartment, which they entered using a battering ram. Taylor’s boyfriend, Kenneth Walker, 27, who said he feared intruders, fired a shot with a legally owned gun, striking Mattingly. The officers fired back, and Taylor was struck five times.

Officer Brett Hankison was terminated in June in a letter from the department that alleged he “blindly” fired his weapon 10 times into Taylor’s apartment. Mattingly and Officer Myles Cosgrove, who also fired into Taylor’s apartment, have been placed on administrative leave.

Cameron’s office began investigating the shooting after Louisville police turned over the results of an internal probe in May.

A decision about charges could hinge upon an interpretation of Kentucky’s “castle doctrine.” Legal analysts have said the law allows someone to use lethal force if they fear for their life when faced with a possible aggressor. But Kentucky’s castle doctrine has an explicit exception for situations in which “a peace officer . . . enters or attempts to enter a dwelling, residence, or vehicle in the performance of his or her official duties, and the officer identified himself or herself in accordance with any applicable law.”

Fischer (D) said Tuesday that he does not know when Cameron will announce his decision in the case, but he signaled it could be imminent.

“We don’t know when the announcement will come, but we must prepare for it,” Fischer said. “Our goal is ensuring space and opportunity for potential protesters to gather and express their First Amendment rights after the announcement.”

Fischer said the city will close some streets in downtown Louisville to vehicular traffic, and he said that his emergency order gave him the power to impose a curfew. Kentucky Gov. Andy Beshear (D) has said he is prepared to deploy the National Guard and state police to support Louisville police.

Meanwhile, anticipation gripped the city and those involved in the Taylor case.

“This should’ve been an easy indictment,” wrote Taylor family attorney Sam Aguiar in a Facebook post Tuesday. He has accused the officers of recklessly firing bullets into Taylor’s apartment.

“Our city is on edge,” he wrote. “I’ve been pacing for eight hours today.”

On Tuesday afternoon, downtown streets were mostly empty. Many city workers and office employees were ordered to stay home in anticipation of possible unrest related to Cameron’s decision. Downtown hotels were turning away guests, and many parking garages were closed within five blocks of the city’s Hall of Justice, where a small crowd gathered near a makeshift memorial to Taylor.

Taylor’s mother, Tamika Palmer, visited the protest scene Tuesday afternoon.

“We’ve been waiting six months. Why should this day be any different?” she said, adding that she did not want to talk anymore, because it had been a difficult day emotionally.

Over the summer, amid the nationwide protests after the killing of George Floyd in Minneapolis, Taylor’s story became a defining symbol of how Black women also have suffered from police violence and systemic racism.

Celebrities including Oprah Winfrey and WNBA players took up calls for justice to be served in Taylor’s case, plastering her face on billboards and emblazoning her name on uniforms. At the Emmy Awards on Sunday, several nominees wore T-shirts that paid homage to Taylor.

Last week, Taylor’s family settled a wrongful-death lawsuit against the city for $12 million, among the highest payouts for a police shooting in U.S. history.

The settlement also required several changes to how city police execute search warrants: Commanders will be required to approve all warrant applications that are submitted to a judge, and police will have to conduct a detailed risk assessment before applying for a warrant. At least two officers will have to turn on their body cameras when they are processing money seized during an investigation. And officers will receive up to two hours of paid time to do community service in Louisville.

The city also has banned no-knock warrants.

But many protesters, as well as Taylor’s family, have focused on criminal charges for the officers involved in the raid. Benjamin Crump, an attorney for Taylor’s family, called on Cameron to charge them with second-degree manslaughter, at a minimum.

“To not have an indictment happen in this city is to say that no matter how much we pay, no matter how much reform we do . . . we’d rather cover it than to deal with the issue,” Tamika Mallory, co-founder of the social justice group Until Freedom, said at a news conference last week, according to the Courier-Journal.

Wicker, however, noted that his client Mattingly “was shot and severely wounded while serving this warrant.” He described the officer as “hopeful that this matter moves forward quickly.”

In his email Tuesday, Mattingly said that regardless of the charging decision in the Taylor case, “I know we did the legal, moral and ethical thing that night.” He added, “It’s sad how the good guys are demonized, and criminals are canonized.”

He wrote witheringly of “pencil pushers at the top” being “too scared to hold the line” and said police officers were placed in a position where if they “make a mistake” during a stressful moment, the department and FBI “go after you” while “the criminal has total autonomy.”

But with federal buildings and courthouses now boarded up and with dump trucks blocking access to some areas, Louisville residents on Tuesday were not optimistic that violence can be avoided if Cameron declines to charge the officers.

“We teach that when you do something bad there are consequences,” Christina King, a 44-year-old mother of four children, said as she looked at the boarded-up federal courthouse. “This is not what a celebration looks like. This looks like a war zone.”

Craig and Berman reported from Washington. Marisa Iati and Teo Armus in Washington contributed to this report.