CNN — (CNN) -- James "Whitey" Bulger's defense lawyer continued hammering away at one of the government's star witnesses in a Boston courtroom Wednesday, trying to portray the convicted killer as a pathological liar who should have called it quits and gone to the electric chair when he had the chance.
"Why not take the death penalty and get it over with?" Bulger attorney Hank Brennan asked Steven Flemmi.
"I was dead either way," responded the Bulger henchman, who has spent five days on the witness stand. Flemmi said he decided to cooperate with the government to spare his friends and family from having to suffer through endless trials: "I took the path of least resistance."
Key to any deal, he said, was testifying against his former crime partners. "I was facing life-in-prison, plus 30-year consecutive sentences, plus the electric chair in two states," he said, describing his testimony as non-negotiable and a package deal, "It was a global situation."
Flemmi pleaded guilty in 2003 to 10 murders.
Bulger's lawyer challenged Flemmi, saying he caved because he couldn't handle conditions "in the hole" in solitary confinement, on a cold floor in a 6-by-6-foot cell, with a ¼-inch slit to look outside.
"I'm a human being. I'd like to have a chair," Flemmi said.
When he complained about having no TV, prosecutor Fred Wyshak jumped up: "I object. It's not the Hilton."
After his deal, Flemmi was moved to a more comfortable, undisclosed facility.
Throughout the trial, Bulger's lawyers have tried to show that as FBI informants, Bulger and Flemmi were protected by rogue FBI agents up and down the chain of command. Without that protection, the duo's reign of terror would not have been as successful or lasted as long as it did, from the early 1970s through the mid-1990s.
After he was arrested in January 1995, Flemmi tried arguing he had been given immunity for his criminal activity by FBI agents who looked the other way. One of them, disgraced agent John Connolly, was convicted of federal and state crimes and is serving 40 years in Florida.
Brennan has been relentless in his questioning of Flemmi, referring to him as a rat.
"A rat is someone who scurries around and feeds on other people," Brennan pointed out.
Flemmi defended his relationship with the FBI, saying both sides benefited: "It was quid pro quo, survival."
When asked whether the FBI agent Connolly ever suggested someone be killed, Flemmi answered, "He gave us information and we acted on it."
U.S. District Judge Denise Casper is reviewing the 30-person witness list submitted by Bulger's attorneys. Many can testify about Bulger's role as an informant but not about the federal murder and racketeering charges he faces. She's expected to rule on which witnesses are relevant to Bulger's defense.