Phil Connor is the boss of a loading crew at the meatpacking factory where Ona works. He is also a sadist and a rapist. He forces Ona to have sex with him and then intimidates her into keeping silent. He has authority in Packingtown because he is a friend of Mike Scully, a major political power in the area. So, Connor warns Ona that if she tries to tell anyone what he has done to her, Connor will make sure that Jurgis and Marija lose their jobs. Connor goes further than that: he blackmails Ona into working at his partner Miss Henderson's brothel. So Connor is a classic example of someone who abuses his power over others for his own personal profit.
Jurgis tries to remedy the situation, first by attacking Connor physically and then by testifying in court about what Connor has done to Ona. Connor has connections, though, and the judge believes Connor's lies without question. Jurgis goes to jail for attacking the man who bullied his wife into prostitution. The problem with Chicago business is that it has invaded every part of the city's social structure. It has even contaminated the agencies that are supposed to control and restrict business: the public offices and the court system. So there is literally nowhere for Jurgis and Ona to turn to seek help against Connor's abuse. The tight relationship between money and power in the American business world is Sinclair's primary target here.
Connor reappears by chance a second time later in the novel. This time, Jurgis is riding high. He has helped Mike Scully arrange an election and he is a foreman at one of the meatpacking plants after a long strike. Overconfident, Jurgis attacks Connor a second time as soon as he claps eyes on him. But Jurgis has overestimated his new power. His connections are no match for Connor's friendship with Mike Scully and membership in the political organization the "War Whoop League." So Jurgis has to skip bail to avoid prosecution and a year's prison sentence. Once again, what matters in these corrupt courtrooms is not justice, it's influence. The higher up on the totem pole you are, the more immune you are from any kind of legal punishment. Connor is basically immune, which means he feels free to do whatever he wants.