FORT LAUDERDALE, Fla. (CBSMiami/AP) — A key witness in the murder trial of Gus Boulis, the prominent South Florida businessman killed in 2001, took the stand Wednesday.

Dwayne Nicholson, formerly handled security for Anthony “Little Tony” Ferrari, told the judge that Ferrari mouthed the words “you’re a rat” and other things Nicholson took as threats.

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Nicholson was in court to testify that Ferrari and Anthony “Big Tony” Moscatiello initially wanted him to kill businessman Konstantinos “Gus” Boulis during a struggle for control of the SunCruz Casinos gambling fleet.

“Can I ask you a question?” Nicholson asked Circuit Judge Ilona Holmes outside the jury’s presence. “Is Tony Ferrari allowed to threaten me? First thing he called me was a rat.”

Holmes responded that he was not and urged Ferrari’s attorney, Christopher Grillo, to rein in his client.

“That’s a form of intimidation. It can be used against him as conciousness of guilt,” Holmes said. “He can’t do things in this courtroom and think it’s going to go unnoticed. You can’t make threats in this courtroom.”

Moscatiello, 75, who is reputedly linked to New York’s Gambino crime family, and the 56-year-old Ferrari could get the death penalty if convicted of first-degree murder in Boulis’ shooting death. Prosecutors say they arranged for a mob hit man to ambush Boulis in his car on a downtown Fort Lauderdale street.

After Ferrari’s threats surfaced, the jury was brought back into the courtroom and Nicholson repeated what he saw. Prosecutor Gregg Rossman asked if Nicholson, who said he is 6-foot-1 and weighs 250 pounds, felt intimidated.

“I’m still testifying. I’m going to be all right,” Nicholson replied.

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Nicholson testified that he was promised a well-paying share of the security work at SunCruz when it was sold by Boulis to New York businessman Adam Kidan and his partner, then-high profile Washington lobbyist Jack Abramoff. Nicholson said Ferrari told him “the family” had bought the 11-ship fleet.

“Meaning the Gambino family,” Nicholson testified. “Tony was saying he was (former Gambino boss) John Gotti’s nephew and that he’s part of the family.”

Investigators have said that Ferrari is not Gotti’s nephew. Nicholson said at a meeting at Ferrari’s Miami Beach office, Ferrari said their security contract was in jeopardy as long as Boulis was alive.

“Little Tony told me they needed Gus taken out. That was his exact words,” Nicholson said. “That was his way of telling me I would have to do it.”

Nicholson said he refused: “I could break his leg, I could hurt him, but I can’t kill him.” And he said Ferrari replied, “Well, we’ll figure out something.”

Nicholson contacted homicide detectives to tell what he knew about the plot against Boulis the day after the killing.

Kidan and Abramoff bought SunCruz for $147.5 million but Boulis kept a 10 percent share, triggering a power struggle that prosecutors say led to his death. Kidan and Abramoff later pleaded guilty to federal fraud charges stemming from the transaction and did time in prison. Abramoff separately was convicted of corruption charges in a Washington lobbying scandal that led to 21 other convictions.

Earlier Wednesday, police experts testified that Boulis was fatally shot with a .380-caliber handgun at close range. A witness previously said Boulis was shot in his car on a Fort Lauderdale street by a man who pulled a car alongside. The experts said four shell casings were found.

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