THE LOCAL Ironworkers union under longtime leader Joseph Dougherty didn't function like a legitimate labor union, but acted like the mob, federal prosecutors say.

"Both criminal enterprises existed and operated through a pattern of fear, violence, and intimidation," Assistant U.S. Attorney Robert Livermore wrote in a trial memorandum filed yesterday. "Both criminal enterprises used that well-earned fear to extort money from businesses."

Dougherty, 73, of Bustleton, business manager of Ironworkers Local 401 from 1998 until early last year, faces trial in federal court starting Monday on charges of racketeering conspiracy, arson-related offenses and extortion. His 11 co-defendants have pleaded guilty, leaving him the lone defendant in the trial.

In the trial memo, Livermore likened the union under Dougherty to "the mafia" and said Dougherty was its "don" or "undisputed leader." Another union member had even described Dougherty as the "Jimmy Hoffa" of the union, the memo says - a reference to the powerful Teamsters leader who disappeared in 1975.

The government is expected to try to show during the jury trial that although he didn't personally commit them, Dougherty approved of acts of violence, including arson and extortion, committed by other union members against nonunion contractors as a way to force them to hire Ironworkers members.

"Dougherty wanted to control all of the ironwork being performed within his territory," the prosecutor wrote. "The motivation for Dougherty's crimes was financial. Not only did the individual ironworkers receive the wages and benefits from the non-union contractors, but the Ironworkers Local 401 received a percentage of that income as well."

The prosecutor said Dougherty raked in more than $200,000 from the union each year. But because of the 2008 financial crisis and other factors, the union suffered financially, and membership fell from more than 1,000 members in the early 1980s to fewer than 700.

The feds' memo says Dougherty "rose to power from very humble beginnings." After growing up in the Abbotsford Homes housing project in East Falls and graduating from Cardinal Dougherty High School in 1960, he joined the union in 1966.

Dougherty became the union's financial secretary and treasurer in 1981 and acted as its apprentice coordinator. He was so "devoted" to the union, which became his family, that he worked late at night "counting the plates and the spoons in the union hall to make sure the count was correct," the feds' memo says, citing what other members have said.

Over the years, Dougherty developed his political skills, outmaneuvered rivals and attracted supporters, and in 1998 defeated his rivals to become the effective head of the union, the memo says.

As the union's leader, Dougherty considered anyone from outside who took ironwork jobs - whether nonunion workers or members of the carpenters union - to be thieves, prosecutors contend.

"Nightwork" - or crimes committed on behalf of the union - was not invented by Dougherty or his co-defendants, but the union under Dougherty "took nightwork to a new level," making it a "pattern of conduct," not just a few isolated incidents, Livermore wrote.

And because of the union's financial woes, Dougherty and his co-defendants "ratcheted up the level of violence against non-union contractors and other trade unions to force them to hire more union ironworkers," the feds contend.

Although the "calling card" of the Ironworkers was "smashed anchor bolts" at nonunion construction sites, Dougherty and his business agents came up with a "new tool" in July 2012 - a small, portable acetylene torch to cut metal with fire and cause significant damage where steel columns were already erected and smashing anchor bolts with sledgehammers would have little effect, the trial memo says.

The first arson committed with the acetylene torch was the December 2012 arson of a Quaker meetinghouse being built in Chestnut Hill, the feds said.

Besides acts of arson or attempted arson, the government is expected to show at trial evidence of numerous extortions committed "with the encouragement and blessing" of Dougherty, the trial memo indicates.

Dougherty's lead attorney, Fortunato "Fred" Perri Jr., declined to comment yesterday on the government's trial memorandum, but has said that Dougherty "maintains his innocence."

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