Arrests and traffic stops are plummeting across the Twin Cities, while the number of people locked in Hennepin and Ramsey county jails has dropped by nearly half.

In a matter of weeks, the coronavirus has brought profound changes to how communities are policed, who is prosecuted and who goes to prison — creating an opportunity for reforms that local civil rights groups and criminal justice activists say are long overdue.

Michelle Gross, of the group Communities United Against Police Brutality, said organizations like hers have for years called for some of the changes now being considered, including pulling back on arrests for nonviolent crimes like burglaries and drug offenses.

"This is a good opportunity for us to really learn what happens by necessity when we can't follow the old paradigms," she said. "We can think about things like restorative justice, not jailing people who have not been proven guilty of any crimes, things of that nature."

The transformations come as COVID-19 has disrupted police and court systems across the nation, forcing officials to take unprecedented steps to combat its spread.

Minneapolis leaders said last month that while officers would enforce the statewide stay-at-home order, the focus would be on education, and police would make arrests only for violations that pose a threat to public health and safety. Other jurisdictions have adopted similar measures, with officers in Philadelphia and Chicago no longer issuing parking tickets in most cases, while Washington, D.C., police are giving verbal warnings to nonessential businesses and people who congregate in large numbers at parks and playgrounds.

At the same time, law enforcement groups in some parts of the country worry that the pullback in policing and release of inmates from jails could lead to more crime.

A review of Minneapolis police statistics showed violent and property crime arrests fell by nearly half over the four-week period ending April 14, when compared with the same period from five years ago.

Arrests for crimes like disorderly conduct, prostitution and driving under the influence decreased to 365 this year, from 784 in 2016. And the number of people detained for petty offenses dropped more than sevenfold, the review found.

The number of traffic stops, meanwhile, also fell or stayed the same during that span, everywhere but on the North Side.

In Ramsey County, daily jail bookings plunged by 74% between the first week of March and the first week of April. A facility that averaged 60 new inmates per day last year and into March dropped to under 20 per day in the midst of Gov. Tim Walz's stay-at-home order, according to a Star Tribune analysis of booking data.

Police departments across the state, including in Minneapolis and St. Paul, were instructed to reserve jail beds for violent offenders and issue citations to those accused of misdemeanor crimes, union officials said.

"I think most cops are all right with that," said St. Paul Police Federation President Paul Kuntz, adding that it's too soon to know whether that practice will stick. "Statistics in and of themselves probably don't tell the full story," Kuntz said.

Reduced arrests, combined with an aggressive push by public defenders to release nonviolent inmates, dramatically thinned the populations inside Twin Cities detention centers — ideal environments for a deadly coronavirus outbreak. State prisons are moving to do the same at a time when the virus is sweeping behind bars, infecting guards and the incarcerated.

"Guess what, the world didn't end because we released someone to go birth at home," said Tonja Honsey, founder of We Rise, a group of formerly incarcerated women pushing for reforms. "I'm hoping this will show everyone that we don't need to lock up all these people."

Meanwhile, the Legal Rights Center and community leaders, in a letter sent last month, called for the release of juveniles and other vulnerable inmates, especially those being held before trial, to home confinement. Prosecutors said early releases are being decided on a case-by-case basis.

Asata Jalloh, a local activist for police reform, said she doubts the crisis will produce any meaningful reforms.

"Because, if they wanted to make change, then change would've been done when people were protesting and when lives were getting taken," she said. "It shouldn't have taken the coronavirus."

With the crisis expected to worsen, local police departments and other law enforcement agencies are shifting their priorities to keeping their officers and the people they interact with healthy, while continuing to deliver public safety services. And some state and county attorneys are telling their staff not to seek pretrial detention for defendants charged with nonviolent felonies or misdemeanors.

Washington County Attorney Pete Orput issued a similar memo raising the threshold for jail bookings last month. He encouraged staff to issue summonses for low-level offenses like shoplifting, minor drug possession and financial card fraud — crimes "none of us like, but nobody is going to get physically hurt over it," Orput said. He advocates that officers "give everything the big or little test," using their discretion about what truly threatens public safety. So far, a 55% reduction in jail bookings hasn't resulted in a noticeable uptick in crime, Orput said.

Still, some worry about greater government surveillance and whether some well-intentioned policies could do more harm than good, particularly as certain jurisdictions start ramping up fines and other penalties for people who break mandated quarantines.

The 2008 financial crisis produced a wave of criminal justice reforms as progressive lawmakers, joined by Republican governors in cash-strapped states, voted to roll back mandatory minimum sentences and other factors that critics say led to mass incarceration, said Ames Grawert, senior counsel at the Brennan Center for Justice in New York. The same could happen after the pandemic subsides, he said.

"They didn't have the perverse luxury of incarcerating more people, because they couldn't afford it," said Grawert. "I think part of what we're seeing is that people are realizing that there are some elements of our criminal justice system that just aren't necessary to ensuring public safety."

But, he added, any changes could be threatened if crime rises, swinging public opinion toward a law-and-order response to public safety.

Chris Uggen, a sociology professor at the University of Minnesota who studies criminal justice, said the changes spurred by the pandemic could have unintended consequences as well.

"The big question for me is that if we stop doing something, will something else pop in to take its place that might work against some of the good that reform was doing?" he said. "For example, if you get rid of cash bail, will some other system emerge to take its place that becomes more onerous against defendants?"