When the outspoken sheriff of Cook County, Ill., Tom Dart, was seeking to eliminate solitary confinement in the jails two years ago, he encountered resistance from a few dozen guards who worked in that unit. So Dart reassigned them all.

Kim Ogg, a longtime defense lawyer elected in 2016 as district attorney of Harris County, Texas, fired nearly 40 of the office's top prosecutors and replaced most of them with defense attorneys.

"I did not feel that I could rely upon the architects of the criminal justice system that I vowed to change," Ogg said in an interview this month.

Change also is coming to the Philadelphia District Attorney's Office, with Larry Krasner, a career civil rights attorney, set to be sworn in Tuesday as the city's top prosecutor. It's unclear what form the first changes may take and when he'll unveil them, but Krasner campaigned on goals including reducing incarceration and eliminating use of the death penalty — developments unlikely to happen overnight.

Prosecutors, law enforcement officials, and attorneys who share Krasner's ideology told the Inquirer and Daily News in recent weeks that changing the culture of the office likely would be among Krasner's most important and challenging tasks — and would define his ability to implement his priorities and make a mark on the criminal justice system.

"For me, at least, it was a lot harder than I thought," Dart said of his attempts to spur systemic reforms. "I just was amazed at how difficult it was to move some of it."

Krasner has yet to specify what structural changes he may make when he inherits the post — which pays $177,000 per year and puts him in charge of 600 employees, about half of them prosecutors. He also has not named any top deputies or other staffers, and a spokesman said decisions would not be announced until Krasner officially takes over for Kelley Hodge, who was appointed interim district attorney after Seth Williams resigned and pleaded guilty to corruption charges.

In an interview last month, Krasner seemed keenly aware of the importance of inspiring buy-in among staff, saying that he's sought to be "direct and honest and truthful about my intentions with that office," and that he does not anticipate — or desire — a mass exodus of panicked prosecutors.

"I'm frankly very optimistic that what we're going to see is tremendous support among the rank and file," he said.

Projecting a message

So far, evidence suggests he could be right. The number of resignations in 2017 is about the same as in years past, according to figures from the District Attorney's Office, and even some of Krasner's most outspoken critics during the campaign — such as the head of the police union — have throttled back on combative rhetoric since his electoral win.

Still, if history elsewhere is any guide, Krasner is likely to face challenges.

Dart was elected in 2006 — before the tide of liberal law enforcers began to rise — but said that as he's sought to reduce the jail population in Cook County, he's encountered regular resistance from the very people he's charged with leading: the union workers who staff the facilities.

The Teamsters there in 2013 took out a full-page newspaper ad ripping Dart, he recalled — just a day before he was set to meet with union leadership. And a union official told 60 Minutes this year that Dart downplayed or ignored staff concerns while appeasing inmates.

Dart acknowledged the fights and the challenges they sometimes cause. But he said he's sought to project a consistent and honest message to his staff, not just explaining his priorities but providing evidence about how his policies are working. He's been reelected twice and recently has been mentioned as a candidate for Chicago mayor. Earlier this month, the jail population reached its lowest total in decades.

"I couldn't try to make my life easier by getting along with everybody and walking away from things that I felt were so patently unjust," Dart said.

Ogg, the district attorney in Harris County, which encompasses Houston, said clear and consistent communication has similarly been key for her as she's sought to reform the office.

When she and other officials announced in February that low-level marijuana cases would no longer be prosecuted, a district attorney in a neighboring county said Harris County would become "a sanctuary for dope smokers."

But Ogg said she sought buy-in from staff on that initiative and others by stressing the policy would save time and money, and would allow prosecutors to focus on bigger and more serious cases.

By explaining decisions clearly and reinforcing them through policies and training, Ogg said, she's started moving the office away from a "lock everybody up" mentality — without sacrificing public safety.

"We put it in writing and we preached internally," she said. "The way to a safer city is higher-quality cases."

Supporters as skeptics

Still, a reality about prosecution — particularly in a city with as much crime as Philadelphia — is that some people will be sent to prison. And in that sense, Krasner may face a unique challenge in building his team: Some of his most fervent supporters may never apply to work for him.

Miriam Krinsky, founder and executive director of Fair and Just Prosecution, which trains and supports change-inclined district attorneys across the country, said being a prosecutor is viewed so unfavorably among some of the most ardent supporters of criminal justice reform that her organization started a fellowship program to try to change the perception.

And Abbe Smith, a defense attorney and law professor at Georgetown University, wrote in 2001: "I am saying to those who are committed to social and racial justice: Please don't join a prosecutor's office." In an email this month, she said she still believes it's hard "to be a 'good prosecutor' in a fundamentally bad system — one that historically criminalizes race and poverty."

At least one Krasner supporter, Ashley Henderson, a lawyer with the West Philadelphia-based Amistad Law Project, said: "At the end of the day, the role of the prosecutor is to lock people up. Personally, I believe that locking people up doesn't actually solve anything."

But even Smith acknowledged that Krasner's office could be an "excellent destination" for lawyers who share his views.

And Dan Urevick-Ackelsberg, a Philadelphia public-interest lawyer who voted for Krasner, said it just may take time for some lawyers to see how the new district attorney approaches the job.

"I did not support Krasner to light a match to the criminal justice system," he said. "I supported him to instill it with a better sense of justice."

‘Transformational’ change

A new sense of justice is certainly part of what Krasner is seeking to offer to his future employees. The job application on his transition website promises "transformational systemic change," and Krasner himself has said he views himself as part of a "progressive" movement.

Paul Hetznecker, a Center City civil rights attorney who defended protesters with Krasner, said being specific about how and when prosecutors will pursue or drop certain cases will likely be among the new district attorney's most important early tasks — and one that will show people in the office how Krasner intends to put his words into action.

"I think he needs to reassure people," Hetznecker said, "that his notion of justice can coalesce with their notion of justice."

Ogg said she's met with Krasner and given him advice on how to handle some early decisions. Dart has not met Krasner but said he would advise him to begin by focusing on the elements and policies he could directly control.

And Ogg, for one, is rooting for Krasner to succeed.

"Elections in prosecutors' offices result in shotgun marriages," she said. "But as long as we can articulate what our vision is and what we were elected to do, then I believe the employees will buy in."