What was Mayor Walsh like as a union leader?

Mayor Martin J. Walsh toured a Dudley Square work site in 2013.Suzanne Kreiter/Globe staff/File/Globe staff

When Martin J. Walsh was elected head of the Boston Building Trades Council in January 2011, he was thrust into the middle of virtually every major construction project in the region, from the Novartis Pharmaceuticals headquarters in Cambridge to the redevelopment of the Old Colony housing complex in South Boston.

As the lead representative for 35,000 union construction workers, he negotiated with developers worried about holding down costs and with labor leaders anxious to protect their members’ benefits and pay.

He wanted developers to hire only union workers — and wasn’t shy about saying so. In exchange, the unions would agree not to strike or slow down work.

“Can he raise his voice? Yes. But who can’t?” said John J. Moriarty, president of a major contracting firm, who dealt with Walsh on a half-dozen construction projects. “He would certainly forcefully want you to get to resolution, but I can honestly say I never felt threatened.”

Walsh’s reputation as a fair-minded labor leader has come under intense scrutiny amid revelations that he has been drawn into a sweeping federal investigation into allegations of strong-arm tactics by unions.

The Globe reported last week that Walsh was recorded on a wiretap in 2012, a year before he was elected mayor, saying he had told a development company that it would face permitting problems on a Boston high-rise unless it used union labor on a project in Somerville.

At one meeting, Walsh brought along the number-two official at the Building Trades Council who, as a member of the Boston Zoning Board of Appeal, could have a say in whether the project could proceed.

Walsh has repeatedly denied exerting any improper pressure. “I wouldn’t do that,” he said Friday. “It’s not my style.”

He is, however, a union man, head to toe. It is hard to overstate the role that organized labor has played in shaping his life and fueling his rise to power.

Walsh got his union card in 1988, when he was 21 and joined Laborers, Local 223. That was the union his father, John, joined in the 1950s, after emigrating from Ireland. His uncle Pat, the union president, had built the local into a clearinghouse for jobs for Irish immigrants. Local 223 is now run by the mayor’s cousin, Martin F. Walsh, known as “Big Marty,” to distinguish between the two.

In a Globe interview, the mayor recalled some ways that unions had helped his family over the last half century.

When he was stricken with cancer as a boy, unions rallied around his parents and helped them pay for the bills. When his father retired, after 50 years in Local 223, he had a pension and health care. And when his father died in 2010, the pension transferred to his wife, Mary. Three years later, when Walsh ran for mayor, unions poured money into his campaign and backed him with volunteers.

Local 26’s Financial Secretary Treasurer Henry C. Green embraced Mayor Martin J. Walsh while union president Brian Lang addressed the crowd at a union meeting in 2014.Lane Turner/Globe Staff/File/Globe Staff

“Somewhere along the road, unions became bad. And I am not going to run away from unions,” Walsh told Boston Herald radio last week. “I grew up in that household, of unions being good, of unions advocating on behalf of working-class people, unions advocating for better benefits, better working conditions. That’s the house I grew up in.”

Walsh himself spent only two years as a laborer before becoming a collection agent for the Massachusetts Laborers Benefits Fund in 1990. A decade later, after he was elected as a state representative, he became recording secretary of Laborers, Local 223, and then president of the union in 2005.

Six years later, he was elected general agent of the Building Trades Council, an umbrella group that represents 35,000 ironworkers, pipefitters, and other unions in 24 communities stretching from Walpole to Reading. The job paid Walsh $174,589 a year, on top of the $76,000 he earned as state representative and the $3,500 he was paid as president of Local 223. It also furnished him with a Jeep and gasoline.

The position, which Walsh held until he resigned to run for mayor in April 2013, coincided with Boston’s emergence from the recession and the beginning of its building boom.

Walsh, though charged with ensuring that developers hired union workers, said he saw himself as a liaison between labor and management. And because only individual unions — and not the Building Trades Council — could call for a strike or picket, he said he had to use softer negotiating tactics.

“If there was a trade having a hard time, I had to keep the door open so I could talk about it,” Walsh said.

Many developers whose projects Walsh now wields influence over as mayor did not return calls or declined to comment on their dealings with Walsh during that era. Several former union colleagues also declined to comment.

But those who would speak on the record said they never saw Walsh bully a developer.

James Coyle, an ironworker who preceded Walsh as head of the council and accompanied him to several meetings with developers, said Walsh approached negotiations as a pitchman, arguing that union workers would deliver a better building than their nonunion competitors.

“He’s selling a product,” Coyle said. “You don’t sell a product with a baseball hat in your hand.”

Coyle said, however, that it was sometimes easy for developers to misconstrue what labor leaders said during negotiations. He said developers often asked him if they were “going to have problems” if they didn’t use union workers. Coyle said he would tell them that union workers would be upset if they saw nonunion workers swinging hammers and welding steel in their neighborhood.

“That’s not a threat,” Coyle said. “That’s reality.”

Moriarty, the general contractor, said he would call Walsh if he was having trouble getting a union to agree to concessions. Sometimes, he would get an earful, too.

“If either side was being unreasonable, he’s tough,” Moriarty said. “No question about it. He’d say, ‘Goddamn it, you need to work with us.’ But as long as there was an effort to get a resolution, he’s very reasonable.”

Martin Walsh, then a state representative, spoke to local union members and labor leaders in 2012.BIZUAYEHU TESFAYE/AP IMAGES/AMERICAN FEDERATION OF GOVERNMENT EMPLOYEES

Walsh’s more conciliatory approach reflected a broader shift in the trades over the last 50 years, away from the two-fisted tactics of old-school labor leaders who viewed developers as adversaries, said US Representative Stephen F. Lynch.

“He’s the referee,” said Lynch, a former president of the ironworkers’ union in South Boston. “He’s got to go in there and talk to the contractors in a way that is more collaborative than the old-style method, which was confrontational. I think he realized the business had changed.”

Carl Valeri, president and chief operating officer of The Hamilton Co., recalled once having to break the news to Walsh that he was going to hire a nonunion contractor to install the heating and air conditioning systems on a housing development in Downtown Crossing. The firm had submitted a bid that was $400,000 less than its union competitor.

Valeri said he braced himself for a backlash from Walsh, but “Walsh looked at his guys and said, ‘What do you expect them to do? It’s $400,000,’ ” Valeri said. “And that was it. He came in. He listened.”