“There’s certainly a line of argument that says, ‘Nope, we’re not going to consider all your individual circumstances, we want to treat everybody the same,’” said Dan Satterberg, the prosecuting attorney for Seattle and a longtime Republican, who instituted an immigration-consequences policy last year and strengthened it after the presidential election. “But more and more, my eyes are open that treating people the same means that there isn’t a life sentence of deportation that might accompany that conviction.”
With that in mind, his office allowed the student to plead guilty to reckless driving instead of driving under the influence. The deal, which included three days of community service and two years of probation — milder than the standard driving-under-the-influence penalty of 24 hours in jail, a few days’ community service and five years’ probation — did not jeopardize her protected status.
But many prosecutors remain wary, hesitant to meddle in what they regard as the federal government’s business and even more reluctant to depart from what they say is a bedrock principle of the system.
“There’s probably hundreds if not thousands of issues that I suppose we could take into consideration,” said Brian McIntyre, the county attorney in Cochise County, Ariz., “and when we do that, we necessarily wind up not being as fair to someone else.”
Cochise prosecutors are not supposed to consider the collateral effects of a conviction, whether it be to a child custody case or a military career.
If he made accommodations for an immigrant, Mr. McIntyre said, he felt that he would also owe a citizen in similar circumstances the same option, “because is he not being, essentially, negatively impacted by his U.S. citizenry?”
A criminal record often has different stakes for an immigrant than it does for a citizen. It can mean losing a green card or being barred from citizenship. Those who lack legal status can lose any chance to gain it. Those with legal status, as well as those without, can face automatic deportation.
In many cases, the city-and-state-level changes dovetail with broader criminal justice reforms that were already underway before Mr. Trump took office.
But to the administration, policies that help noncitizens duck immigration penalties are tantamount to an assault on the rule of law.
“It troubles me that we’ve seen district attorneys openly brag about not charging cases appropriately under the laws of our country,” Attorney General Jeff Sessions said in April.
The local efforts to help immigrants may not always work. The Trump administration has made clear that anyone without legal status may be deported, regardless of whether they have been convicted of a crime.
But reducing criminal penalties can help immigrants by keeping them out of jail, which can make it more difficult for Immigration and Customs Enforcement to find them, or by preserving their options in immigration court.
In May, Denver stopped imposing a maximum jail sentence of 365 days for some lower-level crimes, like shoplifting. A conviction with a potential sentence of a year or longer — even if the actual sentence is far shorter — can disqualify noncitizens from most forms of legal status or render them deportable.
“Whether you committed a physical assault on someone or were caught urinating in the park, you were subject to the same maximum penalties, which doesn’t make sense,” the mayor, Michael B. Hancock, said in an interview.
The Denver shift builds on state laws in California and Washington State that cap misdemeanor penalties at 364 days. That ceiling applies retroactively in California, a major benefit for people detained by the immigration authorities over old convictions.
Immigration lawyers say they frequently see immigrants stripped of green cards or visas over convictions for lower-level crimes, exposing them to deportation.
“Not only do you do your time and pay your fine under criminal court,” said Jeannette Zanipatin, a lawyer at the Mexican American Legal Defense and Educational Fund, “but you’re literally banished from your family and everyone you know.”
In some states, interventions have come from as high up as the governor’s mansion. In recent months, Democratic governors in Colorado, Virginia and New York have tried to help immigrants facing deportation by pardoning their old crimes, though the results have been mixed. One was released after a pardon, but another has been deported and a third remains detained.
Prosecutors who take immigration status into account say this consideration will not be extended to serious or violent crimes. They argue that showing flexibility in nonviolent, minor cases will help build trust with immigrants in their communities, making them more likely to report crimes and serve as witnesses.
The acting Brooklyn district attorney, Eric Gonzalez, went further than most in April, when he announced that his prosecutors would begin notifying defense lawyers about the potential immigration fallout of their clients’ cases and that he would hire two in-house immigration lawyers to consult on prosecutions.
Days later, the state’s attorney for Baltimore, Marilyn J. Mosby, said she had told her staff members to use their discretion when it came to cases with an immigration factor, considering defendants’ prior records and community ties.
“There’s no set standard,” she said. “You have to base it on everything that’s in front of you.”
It is not yet clear what that will look like in Baltimore or Brooklyn. But in Santa Clara County, Calif., whose district attorney was among the first to outline an official policy, prosecutors often allow a noncitizen to plead guilty to a lesser charge in exchange for more jail time or probation.
“If we’re giving something, we’re going to get something,” said the district attorney, Jeff Rosen.
California law now requires immigration consequences to be factored into criminal cases. The state has also passed a law allowing people to erase or revise old convictions if they successfully argue that they were not advised at the time that a guilty or no-contest plea would endanger their immigration status.
Occasionally, cases involving noncitizens have boomeranged on local officials. In April, Mr. Rosen’s office was plunged into a controversy surrounding a domestic-violence case in which a green-card holder from India was charged with felony domestic violence against his wife, a citizen, but ultimately pleaded guilty to lesser charges. The woman has criticized the plea deal as too lenient.
Although prosecutors considered the potential loss of the man’s green card in negotiations, Mr. Rosen said, they felt there was not enough evidence to prove the initial charges in court.
In Boston, a suspect in the double murder of two physicians in May, a legal resident from Guinea-Bissau, had been able to keep his green card despite robbing two banks in recent years after his lawyer negotiated a plea deal that allowed him to plead to larceny instead of unarmed bank robbery. The sentence he received from a judge was also one day short of the 365-day threshold that could have led to his deportation.
But backlash has been infrequent, and prosecutors have continued to take immigrants’ status into account.
Luke Larson, the deputy prosecutor on the case of the Washington State student charged with drunken driving, said several factors favored a milder charge, including her strong academic record and lack of a criminal history.
Most unsettling, for him, was that she had not been back to her home country since she was a toddler. She got the deal.
“It’s easier to say, ‘I don’t want to know about the potential immigration consequences, and I don’t care,’” said his boss, Mr. Satterberg. “It’s harder when you want to know. Then it does require you to know more and to be more creative and to take more of a risk with the case.”