Sabotage, arson, raids, threats and intimidation just a few of the acts.
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Former head of the Philadelphia Ironworkers union Joseph Dougherty was sentenced Monday to 19 years in prison for orchestrating a violent campaign against nonunion contractors.

“His leadership led to a lot of damage,” U.S. District Judge Michael Baylson said in court, according to The Philadelphia Inquirer. “It led to a lot of crimes and it continued the bad reputation Philadelphia has for tolerating union violence.”