The former head of a local Teamsters union reluctantly pleaded guilty Thursday to a federal attempted extortion charge for using strong-arm tactics against a TV production crew in a case with ties to City Hall.

Mark Harrington, 62, is one of five Teamsters members accused of roughing up production crew members taping the “Top Chef’’ television show at Steel & Rye restaurant in Milton in June 2014. They were charged with attempted extortion for allegedly using strong-arm tactics to extort jobs from the television show under the threat of disrupting filming. Prosecutors said the threats put the show’s producers in “fear of economic harm.’’

All of the defendants initially pleaded not guilty. But Harrington agreed to a deal with prosecutors that would require he spend no more than two years on probation and serve no jail time. Harrington, the former secretary-treasurer of Local 25, faced more than two years in prison under sentencing guidelines. US District Judge Douglas P. Woodlock said Thursday that he will review the agreement before sentencing Harrington on Dec. 15.

Harrington told Woodlock he was only seeking jobs for union members.

“That’s our [prerogative] as a union to impact a company through economic harm,’’ he said at the plea hearing.

Harrington and the other defendants had previously argued that they did not commit a crime, and that they were picketing — what they characterize as a protected union activity.

But prosecutors argued that the defendants were not covered by collective bargaining rights because they did not have a collective bargaining agreement with the production company, and the jobs they were seeking for union members were already filled.

The case was connected to City Hall when prosecutors alleged in an indictment last year that a top official in Mayor Martin J. Walsh’s administration warned two Boston restaurants that the union would picket if the restaurants agreed to host the show. The Boston restaurants then canceled agreements to host, and the taping was moved to Steel & Rye.

There, the five Teamsters members allegedly intimidated and harassed crew members, blocked delivery trucks from entering the property, chest-bumped crew members, and slashed their car tires, prosecutors said.

“Most of the staff said they felt scared, threatened, intimidated by their actions,’’ Assistant US Attorney Laura Kaplan said.

The City Hall official, Kenneth Brissette, the city’s head of tourism, was not charged in the case with the five Teamsters members, but was accused in a separate indictment of trying to withhold permits for “Top Chef’s’’ filming. He and another city official, Timothy Sullivan, were also charged with threatening to withhold permits for the Boston Calling music festival unless organizers hired union workers. They have pleaded not guilty.

Harrington’s lawyer, Robert Goldstein, earlier filed a motion to have the case dismissed, saying the union members were engaging in their constitutionally protected right to protest for better wages and jobs. US Magistrate Judge Marianne Bowler rejected the request, though defense lawyers filed objections to her ruling with Woodlock, the presiding judge. A similar case questioning the rights of union members is pending before the federal appeals court in Boston, and that court’s decision could influence the outcome of Harrington’s case. It is not known when the appeals court will issue its decision.

Woodlock said he would allow Harrington to withdraw his guilty plea if he chooses to dismiss the charges. Otherwise, he will sentence him in December.

He asked Harrington, however, whether he was seeking to replace the crew members who were already hired, or was he simply looking to obtain jobs for Teamsters members.

“I was trying to get them to hire union members, with no regard for the other [workers],’’ Harrington said.

Milton J. Valencia can be reached at milton.valencia@globe.com. Follow him on Twitter @miltonvalencia.