CAMBRIDGE — Michael Sullivan, who is vying to become the next Middlesex district attorney, comes from a long line of politicians and is the latest leader from a family that has held office in the county since 1936.
But his service hasn’t prevented him from earning money in the private sector. From a family trucking business, making legal referrals, and consulting work performed while serving as clerk of Middlesex courts, Sullivan earned more than $1.6 million between 2009 and 2013, according to tax records provided by his campaign and financial statement disclosures he filed with the state Ethics Commission. His annual salary as clerk of courts as of 2013 was $110,220.
“I have had side businesses,” Sullivan said. “Many people do to support their family. Mine happen to be more lucrative than others.”
As he prepares for the Sept. 9 Democratic primary, Sullivan, a married father of two teenage sons, will rely heavily on a family legacy of campaigning and field-organizing that observers say will be one of his greatest assets when he tries to unseat Middlesex District Attorney Marian Ryan, who was appointed in 2013 by Governor Deval Patrick.
Stocky and affable, Sullivan, 54, grew up in Cambridge, where seniors often recognize him and his twin brother, who they remember being carted around by their late father, Walter, the former mayor, and their uncle, Edward, the one-time clerk of courts.
During a campaign stop at Harvard Yard on a sunny August afternoon, Sullivan joked with college deans, danced the electric slide, and hugged women in their 70s and 80s who had gathered for an annual luncheon.
“Vote for him or I’m moving,” Mae Sullivan, 77, and no relation, told her lunchmates as they finished their grilled chicken and mixed greens. “I’ve been voting Sullivan since I could vote.”
After about 14 years on the city council and soon after he was elected clerk of courts in 2006, Sullivan began consulting for Alexandria Real Estate Equities, a developer that would eventually build a series of office and apartment buildings around Kendall Square.
According to state filings from 2007 to 2009 Sullivan was paid between $75,000 and $130,000 for that consulting work.
Gregory Sullivan, a former inspector general who is not related to the candidate, said Michael Sullivan should have sought guidance from the Supreme Judicial Court, which establishes ethics rules for the clerk of courts, before accepting the consulting role.
“For a clerk of courts to accept a consulting job for real estate development in his jurisdiction that could potentially wind up in the courts in my opinion is problematic,” said Gregory Sullivan, who is now a researcher at the Pioneer Institute, a conservative think tank.
The SJC instructs clerk magistrates not to enter into any business relationship that could create a conflict of interest or “detract from the dignity of the office.”
Michael Sullivan said that if the company had gone to court, he would have recused himself from handling the cases and would have immediately informed the chief justice of the court about his role with Alexandria.
He said he did not seek an opinion from the SJC because it was clear to him the job didn’t compromise his elected position. At no point did he have to lobby for the company or its projects, Sullivan said.
“They approached me and hired me based upon my knowledge of the community, of Cambridge,” he said.
Sullivan is a triple Eagle: he graduated from Boston College High School, Boston College, and Boston College Law School.
He returned to Middlesex County in 1986, where he worked as a prosecutor for 4½ years, then spent three years as an assistant attorney general before going into private practice. In 1993, he ran for city council and was ultimately elected to 7 terms, during which he also served as mayor, a largely ceremonial position in Cambridge.
When he was still mayor, Sullivan referred a former client’s personal injury case to a friend. The case settled for about $6.2 million, according to court records. Tax records indicate that Sullivan received about $1.2 million in referral fees. Sullivan also draws income from the family’s snowplow business, for which he has worked since he was 13.
The side businesses have never interfered with his elected positions, Sullivan said.
“The rule of thumb is,” he said, “don’t do anything to screw up your day job.”
Sullivan, who ran for DA in 1998 and lost to Martha Coakley in a three-person race, said he decided to try again after prosecutors encouraged him to run and because of his concern over the large departure of seasoned prosecutors and complaints that the office was becoming less transparent to the public.
“I look forward to making the office what it had been,” he said.
During the campaign, Ryan, who has spent her 34 years as a prosecutor in Middlesex, has characterized him as a career politician. But Sullivan argued that other district attorneys have also taken a circuitous path to the seat.
“You’re running the largest law firm in Middlesex County,” Sullivan said. “It’s about someone being able to manage the office and who understands prosecution.”
Former Middlesex district attorney L. Scott Harshbarger, who hired Sullivan as a prosecutor and also supervised Ryan, said he chose to endorse Sullivan in part because he has held so many public positions.
“You benefit coming to that role with different kinds of experiences and with some sense of accountability to the community that you learn only from running for office,” Harshbarger said. “In my view that’s what makes you a better district attorney.”Maria Cramer can be reached at email@example.com. Follow her on Twitter @GlobeMCramer.