THERE APPEARS TO  be growing interest in the looming contest for Suffolk County district attorney, the first open race for the position in 16 years and an election coming amidst a national wave of rethinking criminal justice policies and a focus on the important role played by prosecutors.

But that heightened public attention is colliding with a challenge facing even the most engaged voters: Identifying meaningful distinctions among a crowded field of candidates, none of whom entered the race with a prominent public profile.

The American Civil Liberties Union of Massachusetts is trying to promote greater understanding of the race – and of the vital role played by district attorneys — through a public information campaign dubbed “What a Difference a DA Makes.” A debate on Thursday organized by the ACLU and a group of other organizations may have gone further than any forum in the race so far to tease out differences among the five candidates vying in the September 4 Democratic primary – Evandro Carvalho, Linda Champion, Greg Henning, Shannon McAuliffe, and Rachael Rollins.

There are no Republicans in the race. An unenrolled candidate who will appear on the November ballot, Michael Maloney, did not attend the debate.

The forum, held at Hibernian Hall in Roxbury before a crowd of more than 400 people, featured a “lightning round” set of questions in which, on several big issues, the five candidates broke into two distinct groups.

Rahsaan Hall, director of the racial justice program at the American Civil Liberties Union of Massachusetts, speaks following a debate among candidates for Suffolk County district attorney at Hibernian Hall in Roxbury. (Photo by Michael Jonas)

McAuliffe, Rollins, and Carvalho all said they supported the elimination of cash bail for defendants who have been charged with offenses but not yet tried, while Henning and Champion said they did not. There was a similar breakdown when candidates were asked whether they would commit to doubling the number of cases sent to pre-trial diversion in their first year in office.

McAuliffe, Rollins, and Carvalho also said they favored elimination of mandatory minimum sentences for all crimes except murder, while Henning and Champion said they did not.

Henning, an assistant district attorney in charge of the gang unit, was alone among the field in refusing to commit to not prosecuting any simple drug possession cases. He also was the only candidate who balked at the idea of ending all civil forfeiture cases in which property can be taken before a conviction.

All the candidates pledged to make data publicly available, broken down by race and ethnicity, on all prosecutions and cases sent for court diversion if they are elected.

All five also agreed that policies and practices of the Suffolk DA’s office have contributed to racial disparities in incarceration rates. Henning and Champion tried to add more detail to their answers, with Henning saying everyone is responsible for the disparities, but he was cut off by moderate Callie Crossley of WGBH.

Some questions were directed initially to a specific candidate, targeting what may be their Achilles heel by zeroing in on a topic that could raise doubts about their candidacy in the minds of some voters.

Rollins, a former state and federal prosecutor and general counsel for the state transportation department and Massport, has touted her reform outlook and commitment to easing the heavy hand applied by the DA’s office and ending inequities in prosecution. “We can change the criminal justice system where we no longer have wealth and racial disparities,” she said in her opening statement.

How, then, she was asked, does she reconcile her reform platform with a record as prosecutor that included defending immigration enforcement agencies in cases would lead to deportations and a civil forfeiture case in which she argued for the government’s right to seize the home of a couple where police found marijuana plants growing?

Rollins drew a distinction between those who carry out the policies of an office and those who set that course. She reported to higher-ups in the cases that were cited, she said. “As the district attorney, you set policy,” said Rollins. “And I’m trying to run so that I can make policies for this state that are consistent with what the Legislature and the voters have said.”

Rollins said she spoke up internally against certain policies while a prosecutor, trying to ensure that “the people’s voices were heard behind the wall of the US attorney’s office.”

McAuliffe, a longtime public defender who most recently directed the Boston office of Roca, a Chelsea-based nonprofit that works with gang-involved young men, was asked about criticism that the program did not work closely enough with the black and Latino community in Boston when it launched its effort there.

“We didn’t do it as artfully as we certainly could have, and didn’t listen and learn the way that we should have,” said McAuliffe, who said she was brought in to foster better ties with various partners in the community.

Champion, a former assistant district attorney, was asked to defend her opposition to raising the minimum age for adult court jurisdiction – a popular stand in criminal justice reform circles based on research studies showing that young adults’ brains are still developing until they’re at least 25 years old.

She said 18-year-olds have the right to vote and can be called on to go to war, and should also be held accountable by the court system for their actions. At the same time, Champion emphasized that she believes young offenders should be dealt with based on the individual circumstances of the case.

Carvahlo, a state representative whose district includes parts of Dorchester and Roxbury and a former assistant district attorney, was asked how his limited management background equips him to run the sprawling DA’s office, which has 250 employees, including about 140 attorneys.

He took a stab at it by citing his mentoring of younger assistant DAs during his time as a prosecutor and oversight of his State House office, but then pivoted to appeal to the idea that what voters most want is a different direction in the philosophy of the DA’s office.

“When people talk about Dan Conley,” he said of the outgoing Suffolk DA, “the last thing you’ll hear is he’s a bad manager,” said Carvalho.

Henning was asked whether, as a prosecutor, he’s ever threatened a reluctant witness with intervention from the state’s Department of Children and Families or subpoenaed someone to testify even if it might put their life at risk.

“Absolutely not,” Henning said of the idea of threatening a would-be witness. As for subpoenaing someone to testify in a case, he said that can only take place with the order of a judge and that there are “very, very limited circumstances where this would happen.” He cited a case involving the murder of a 16-year-old boy where prosecutors sought to compel testimony from a witness.

As wrenching as that may be, said Henning, “We also have to worry about and think about the mother of the person down the line who is injured or killed by the person who gets off because we are not able to put a case together.”

The four candidates who have worked as prosecutors all talked of ways they would work, if elected, to make the DA’s office more responsive to the communities hit hardest by crime and to look for opportunities give second chances to deserving defendants to avoid the entanglements in the system that can hold back those looking to get onto a positive path.

McAuliffe, the lone candidate who has never worked as a prosecutor, sought to turn what might be a disqualifying liability in any earlier era into the lead argument for her candidacy. She said the record of the Suffolk DA’s office over the last four decades, when it’s been led by three different experienced prosecutors, is one of “mass incarceration” and “systemic injustice.”

“It is clear that an experienced prosecutor is not the answer to our problems,” she said.

Carvalho, who touted his role sponsoring some of the key elements of the recently passed criminal justice legislation, made a frank appeal for someone from Boston’s minority community, where a disproportionate share of cases originate, to take the reins of the DA’s office. “It’s time for someone who grew up in this community, someone who lives in the community, who’s been working for the community to be the next district attorney,” said Carvalho, a Cape Verdean native who came to the US as a teenager with no knowledge of English.

Rahsaan Hall, director of the racial justice program at the ACLU, said after the debate that the big turnout shows “the level of accountability that community expects from these candidates and whoever eventually becomes the district attorney.”

He said the tough questions put to each candidate based on something in their own record were part of that drive to accountability. “We were intentional about having something asked specifically to the candidate because they all come with their baggage and their own issues,” said Hall. “Because of the approach that we took, you see the way that these questions kind of got a little sunlight between some of the candidates.”