Police officers are handing criminal citations to people whom they once would have taken to a cell. Officers might let a motorist slide through a stop sign without pulling the driver over. Some calls they once sped to are being handled by phone.

And officers who once took a moment to kick a ball with kids or chat with a pedestrian now keep distant — and warn others to do the same.

The job of policing in small towns and big cities changed abruptly as the novel coronavirus started its sweep across the country, and officers and the citizenry found themselves sharing the same invisible fear.

In many ways, the mind-set of police turned upside down, with rules and routines adjusted on the fly. The practicality of enforcing some laws diminished as it has become harder to make the personal connections that define community policing.

In the District, police are ordered to break up gatherings to enforce social distancing and are told to use their public-address systems to warn groups — even kids playing — that their actions put them “at risk and could result in severe illness and even death.”

Darnell Garvin, a veteran D.C. police officer, sat in his idling patrol car at a deserted intersection in Northwest Washington on a recent day, listening to his radio as colleagues chased a suspected criminal.

“They’re out there working,” said Garvin, who patrols the Takoma neighborhood. But out his window he could see a closed ballfield and recreation center, and the normally bustling street lacked the midday vibe of pedestrians and motorists competing for space. No serious crime will be ignored, police stress, but officials in many places say it is a time to ease up on the small things.

"A minor traffic infraction, like no right turn on red or going through a stop sign, we play by California rules," Garvin said. "There is no sense of putting yourself in harm's way for a minor infraction."

Police in the District have expanded the types of illegal activity that qualify for citations, meaning more people who are handcuffed and taken to a cell at a station house get sent home with a ticket and a promise to come to court later.

“The last thing a police officer wants to do today is make an arrest unless they absolutely have to,” said Chuck Wexler, the executive director of the Police Executive Research Forum, which advises law enforcement agencies on best practices. “Police officers are trying to do what the rest of America is doing, put distance between themselves and other people.”

A Washington Post analysis of data from the past three weeks shows that amid the pandemic, overall violence has decreased in the District and in other cities, including Atlanta, Baltimore and Boston. Crime is up in some categories in the District, including assaults.

The number of newly arrested defendants who made initial appearances at D.C. Superior Court has dropped significantly, with just 22 on the “lockup list” on Wednesday. Typically, as many as 100, and sometimes more, defendants are set to have those initial hearings each day. District officials said the number of inmates in the city jail has dropped in half to 1,700. Still, police worry crime could increase as tensions rise.

All over, activities that bring the public and police together have been sidelined, such as the District’s popular “Coffee with a Cop” and neighborhood walks with the chief. On Tuesday, D.C. police held their first community crime meeting by conference call for residents on Capitol Hill. Twenty-five people joined.

Dustin Sternbeck, a D.C. police spokesman, said it has become “a balancing act” for officers trying to continue community outreach even as they practice social distancing. “We certainly don’t want to fracture any relations over this,” he said. “This is unprecedented for us, too.” To remind residents they are still at work, D.C. police tweeted a picture of police dog Lucca with the message, “Don’t forget to call when you need to. We’ll pick up.”

But once they do, the changes are stark. Callers to 911 are questioned about symptoms to warn responding officers of possible risk. Officers ask to talk to people outside their homes, and witnesses to crimes may be asked to email statements to detectives. If a crime is not in progress, or a suspect is not there, the call might be handled all by phone.

Law enforcement agencies are trying to protect the public and their own officers to ensure their forces are not depleted. The officers know the threat posed by the coronavirus is real: Five D.C. police officers had tested positive for the virus as of Saturday.

In Miami, health workers take temperatures of officers before they start work and identify the healthy ones with color-coded wristbands. The others are sent home. Other agencies tell officers to report to scattered offices to ensure separation. Police in the District and elsewhere conduct roll calls to mark the start of patrol shifts outside or in parking garages. In Fairfax City, Va., officers have met by group email.

On the street, police are sometimes instructed to ignore laws they once enforced and enforce rules that before never existed. Baltimore suspended virtually all parking restrictions, while Montgomery County quit ticketing motorists illegally stopped outside restaurants to pick up food.

D.C. Mayor Muriel E. Bowser (D) simply said, “I think we’re pretty relaxed on parking right now,” even as she sent police and the National Guard to prevent spectators from gathering at the Tidal Basin to gaze at the cherry blossoms. Later, she told reporters that she saw kids playing soccer on a school field and said she would direct police “to move along people who are not following social distancing.”

Lt. Angelo Consoli, who works in Prince George’s County, said agencies need to be careful to not undermine years of work spent building trust with residents.

“Luckily we haven’t hit the point yet where we had to enforce” social distancing, said Consoli, who heads the county’s police union. But he said that could change and risk creating “another way people can see us in an unfavorable light.”

Anders Johnson, a police officer in Montgomery County, said the situation keeps him in his patrol car more than he would like, instead of talking with pedestrians, homeowners and shopkeepers. It means he is doing less community policing. He misses walking the edges of ballfields and tossing a football with the kids.

“We’re not as interactive with the public as we were,” Johnson said on Tuesday. “We’re still out there. We’re still doing our job. But it’s definitely changed how we patrol.”

On Wednesday, officers with the Maryland-National Capital Park Police said they broke up an outdoor memorial service with up to 100 teenagers and young adults in Bethesda who had lost a friend. The agency tweeted that “while we are sorry for the loss and understand the need to grieve,” it cited the “executive order banning gatherings of more than 10 people to slow the spread of Covid-19.”

Even as they warn others, officers are also adjusting to how they can cope with the new threat while on the job.

Garvin, the officer in Northwest Washington, put on his protective mask for the first time for what he once would have considered the most routine of calls in one of the safest places — picking up a prisoner at a hospital. “That made me feel a little eerie,” he said. “I thought, ‘Now I got to go in there?’ ”

Masks, gloves and protective glasses are not new to cops on patrol, who often deal with people at risk for infectious disease. But they are not always the first priority, even in a time of crisis.

“My job isn’t to do what’s best for me in the moment,” said Officer Matthew Kenyon of the Fairfax City Police Department. “Someone needs my help, that’s my job, and there’s not always time to ‘glove up’ and ‘mask up.’ ”

Kenyon said the virus has not stopped him from community policing. “I can still get out of my car and walk around,” he said. “Just because this is happening doesn’t give us a reason not to do our job.”

Ben Fetting, a D.C. police officer who patrols the Third District, which runs from Adams Morgan to Shaw, called it “business as usual. We’re paid to keep the community safe and to keep it moving.” In some ways, Fetting said, policing got easier.

“Nobody is out,” he said.

Fetting and his wife of 20 years, Meg, have two grown children stuck in their house in Maryland. Meg Fetting, a schoolteacher, said she used to worry about her husband being shot. Now she has a different fear that does not abate when he walks in the door after work.

“I’ve learned to push a lot of worry to the side,” she said of being married to a police officer. “I’ve learned to know that he will come home. Now, it’s that I know he’ll come home, but he could come home and bring a virus to this family.”

Meg Fetting said no matter how many precautions her husband takes, he “doesn’t have a choice to social distance.”

Over this past weekend, she watched in horror as people flocked to the Tidal Basin and police had to shut it down. By Monday, her concern grew to a panic.

“My goodbye was very different,” she said of seeing her husband off to work, recalling “extra hugs.”

She thought, “I don’t want him to go.”

John Harden and Fenit Nirappil contributed to this report.