A nonunion electrical contractor who traded punches with labor leader John “Johnny Doc” Dougherty in January filed a federal lawsuit Monday against him and his local, accusing them of racketeering.

Joshua Keesee, who says Dougherty broke his nose in the fight, contends that he has become a pariah in his trade since the clash, with developers refusing to hire him to avoid antagonizing Dougherty.

Under federal racketeering law, said Clifford E. Haines, one of Keesee’s lawyers, Dougherty and the union would have to pay triple damages if the suit is successful. Such an outcome could net Keesee $450,000 or more.

Frank Keel, a spokesman for Local 98 of the International Brotherhood of Electrical Workers, said the union had no immediate comment on the suit because it had not yet seen it.

He added: “All you need to know about the motive of the lawsuit is that the press received it before we did.”

The civil suit aside, Dougherty has been facing a sprawling federal criminal investigation that some legal analysts have said smacks of a racketeering probe. The investigation became public in August, when FBI agents fanned out to serve search warrants on union offices and homes, and businesses of key union staffers and allies.

The FBI also has been investigating two brawls involving Dougherty that broke out at the same work site in South Philadelphia, including the January clash and one in 2014 during which, the labor leader said, he was hit in the head by a brick tossed by a nonunion crew.

The January brawl also has been part of an investigation by the state Attorney General’s Office. Philadelphia District Attorney Seth Williams referred the case to state prosecutors, saying he faced a conflict due to his political dealings with Dougherty.

In Keesee’s suit, the nonunion contractor says Dougherty has a reputation for being “combative and for intimidating political, business and labor rivals.”

It notes that Local 98 fought the use of nonunion labor at the South Philadelphia townhouse project, purchasing a website domain in the name of the project’s developer and creating an internet site full of derogatory information about the developer.

The union also inflated its 12-foot rat at the site. Keesee said a union business representative, Christopher Owens, told him he was paid $140,000 a year “just for standing outside” and guarding the rat. Keel has confirmed that Owens is a union official paid $143,900 annually.

Keesee said he took up the job wiring the townhouses after the previous contractor said his “guys no longer felt safe.”

He said the brawl unfolded when Dougherty and three other union members, including Owens, confronted him outside the townhouse project. He said Dougherty raised his voice and told him that nonunion workers were not welcome in South Philadelphia.

He also said Dougherty used a racial slur, saying, ” ‘We don’t want n-s here.’ ” Keesee is American Indian. In a March interview, Dougherty adamantly denied making any racial remarks.

In the suit, Keesee, 36, said Dougherty, 55, swung first, breaking his nose. In the interview, Dougherty said Keesee was the aggressor, clobbering a union member in the head and opening up a cut.

A few days after the brawl, Keesee said, someone from Local 98 approached him to say that if he would “forget about” the fight, the union might be able to make up his lost money from the job. Keesee said he refused the offer.