Serra urged the jury to reject the FBI's tactics, prompting Judge Charles Breyer to interrupt his closing argument.
"You cannot pass judgment as to the propriety of the undercover agent's tactics with respect to this case if they are legal," Breyer told the jury. "The court has instructed you that an undercover agent may engage in illegal activities. That is deception."
Prosecutors argued throughout the trial that Chow began plotting to take over the tongs in the early 2000s, and he cemented his power grab with the Feb. 27, 2006, assassination of another tong leader, Allen Leung.
"It was Raymond Chow who benefited the most from Allen Leung's murder," Badger said, noting that Chow then rose to dragon head of the Chee Kung Tong in August 2006. "Six months later, Raymond Chow had the power, the position and the respect. He established himself in Chinatown. Allen Leung was out of the way."
Two of Chow's former associates testified during the trial that he ordered Leung killed. Chow is also charged with conspiring to kill Chinatown rival Jim Tat Kong in 2011 and 2012, and other alleged former associates testified to the rivalry and Chow's order to "take care of Jimmy."
Defense attorney Serra urged the jury to discount the testimony of all the government's witnesses hoping for a lighter sentence in exchange for their cooperation, noting that both murder counts were added to Chow's indictment shortly before the trial's start.
"They knew they were going to lose, and they invested all of this money in a case where their trophy was going to walk," Serra said of the prosecution. "They went to the toilet and they scraped the bowl and they came up with five or six or seven scumbags, and then it turned into a murder case."
Prosecutor Badger said among the lessons Chow learned from his previous conviction was to feign ignorance of the crimes carried out by his associates, but he took kickbacks from his crew, she said, and dozens of thousand-dollar payments from the undercover agent using the name David Jordan.
"Raymond Chow did what any high-ranking member of a gangster racketeering organization does," Badger said. "He connected David Jordan ... gave his blessing. His associates started working, engaging in a wide range of crimes with David Jordan, and Chow was the shot caller."
Prosecutors have over the course of the two-month trial sought to prove Chow's "deliberate ignorance" of hundreds of money-laundering and illicit liquor and cigarette transactions, mostly initiated by the FBI.
Chow's defense attorneys argue that while Chow took money from the agent, he never knew where it came from and consistently denied any interest in crimes on FBI phone and wire recordings.
"Raymond Chow is a man who says one thing but means another," Badger said. "He says, 'No, no, no. No I can’t take that money,' but he took it every time. This is the man who asks you to believe him. He is not the victim here. He is not the world's most misunderstood criminal."
Defense closing arguments are expected to conclude Tuesday. Then jury deliberations begin.