And in Worcester, District Attorney Joseph Early, who has run unopposed every four years since he was elected in 2006, will face a defense lawyer who is calling for a citizens advisory board to ensure that prosecutors are being “fair and impartial.”

In Middlesex County, incumbent Marian Ryan, a Democrat and self-described progressive, has drawn a challenge from her left, a former prosecutor and defense attorney who describes herself as the true liberal in the race.

In Suffolk County, three candidates vying to be district attorney say they believe minimum mandatory sentences for low-level drug offenders should be repealed.

Against the backdrop of last year’s district attorney’s race in Philadelphia, which drew national attention when a former civil rights lawyer with no background as a prosecutor and little support from law enforcement won a decisive victory, a wave of new candidates for top prosecutor positions is emerging, with many vowing to carry the mantle of criminal justice reform.

Amid growing resistance to mass incarceration and racial disparities in prosecutions, district attorney races across the country have taken on prominence. Wealthy donors have made major contributions to reform-minded candidates, and groups such as the American Civil Liberties Union are lobbying voters to pay attention to the usually low-profile races.


“District attorneys will throw their hands up and say ‘We’re not responsible for what society leaves on our doorstep.’ And that’s just not true. They have an important role in reducing those disparities,” said Rahsaan Hall, director of the Racial Justice Program with the ACLU in Massachusetts and leader of “What a Difference a DA Makes,” a campaign to raise awareness about the importance of the job.

District attorneys in Massachusetts run the prosecutors’ offices, where decisions are made about whom should be charged with crimes and which cases should be prosecuted.


Despite the state’s liberal leanings, most Massachusetts district attorneys have largely hewed to a traditional law-and-order philosophy, resisting changes such as limiting mandatory minimum sentences for certain drug offenses and increasing the age of criminal responsibility to 19. And through the years they have faced little, if any, opposition.

Voter interest in primaries for district attorney, where the eventual winner is usually decided, is historically among the lowest for all political races. In 2014, only 60 percent of the 718,000 primary voters in Massachusetts cast ballots for district attorney. Seventy-three percent of the 2.18 million voters cast ballots for district attorney that November.

Hall said volunteers for the ACLU campaign plan to canvass neighborhoods, distribute leaflets, pepper social media with announcements about the various races, and push candidates to debate.

The campaign will not endorse candidates but will put forth a platform of values it wants prosecutors to uphold. Issues are likely to include reducing the number of defendants held on bail while they await trial and the repeal of mandatory minimum sentences, Hall said.

Primaries will be held in September, the Tuesday after Labor Day. Most of the state’s 11 district attorneys do not face challengers yet, but a surprising number of candidates have declared in counties that rarely have contested races.

In Boston, where Suffolk District Attorney Daniel F. Conley has decided not to seek another term, three people have formally announced their intention to run, and more are expected to jump in the race.

State Representative Evandro Carvalho, a Cape Verdean immigrant who was a Suffolk County prosecutor before he was elected to the Legislature, said he is running in part because he wants to see fewer young black and Latino men sent to jail.


“We need a district attorney who understands the difference between a young man who needs a second chance and a violent criminal who needs to go to prison,” Carvalho said in a statement.

Greg Henning, a 38-year-old prosecutor and chief of the gang unit in the Suffolk DA’s office, announced his candidacy last week.

He said he will call attention not only to his law enforcement experience, but to the year he spent teaching eighth- and 12th-graders at Boston Preparatory Charter Public School in Hyde Park.

“It probably used to be a plus to be a prosecutor, but now it might be a disadvantage,” Henning quipped. “I think I’m a different prosecutor than the stereotype of ‘lock ’em up and throw away the key.’ ”

The other declared candidate in Suffolk County is Shannon McAuliffe, a defense attorney and former director of the Chelsea youth center, ROCA.

In an interview, McAuliffe said she would release statistics on arrests, prosecutions, and bail requests to allow the public to judge whether minorities are being disproportionately incarcerated.

“The system works differently for different people,” McAuliffe said. “What you can do is kind of ignore that or you can recognize the system is working differently . . . and say ‘How do I respond to that?’ ”

In Middlesex County, where Ryan has been district attorney since 2013, former Suffolk prosecutor Donna Patalano struck a similar theme, saying reducing racial and income disparities will be a priority.


“We know the numbers of cases that are being prosecuted, but we don’t know anything at all about bail requests or plea deals,” said Patalano, a defense lawyer in Winchester. “We don’t know if the person in Lowell is getting the same treatment as the person in Weston.”

In Worcester, Blake Rubin, an unaffiliated candidate who was a prosecutor in Suffolk, Worcester, and Hampden counties before taking on defense work, is also calling for more accountability as he tries to unseat Early.

Rubin said Early is too insulated from the public. Early has repeatedly rebuffed open records requests and is being sued by the attorney general for denying media requests about prosecutions.

“I think the DA needs to be out talking to the public, to the citizens, holding town hall meetings,” Rubin said. “I’m out on the campaign trail, and one of the questions a lot of people have is ‘What does the district attorney do?’ The general public has no idea who the DA is.”

Incumbents facing challengers defended their records as progressive prosecutors.

“I don’t get the progressive challenge to Marian Ryan,” said her campaign spokesman, Scott Ferson. “To run to Marian Ryan’s left strikes me as hard to navigate.”

He noted that Ryan refused to join nine other district attorneys who opposed doing away with mandatory minimum sentencing laws, although she has not explicitly called for their repeal. She was also one of only two district attorneys who did not sign a letter protesting some of the criminal justice reform changes on Beacon Hill last year.


Through a campaign spokesman, Early said he also believes in reducing the length of minimum mandatory sentences and would consider their repeal, a slight shift from his previous position.

“Criminal justice reform needs to happen in Massachusetts,” he said. “It is critical for the details to be correct, so that the rights of victims and defendants are appropriately protected and balanced.”

Tobe Berkovitz, a marketing professor at Boston University, said the district attorney races are a sign of growing discontent with the status quo. Liberal voters are looking for more full-throated disavowals of Trump policies or candidates who claim to represent populations that are feeling marginalized in the current political climate, he said.

“I just think it’s political angst, and it just so happens that finger is pointing to DAs,” Berkovitz said. “People are angry. They’re dissatisfied and are willing to look at alternatives.”

The irony, Berkovitz said, is that unlike Philadelphia, which was plagued by corruption and where people were jailed at a rate that was twice the national average, counties such as Suffolk and Middlesex already have district attorneys who espouse fairly liberal philosophies.

“Yes, there are differences,” Berkovitz said. “But anywhere else in the country these differences would be a joke.”

Maria Cramer can be reached at mcramer@globe.com. Follow her on Twitter @globemcramer.