The triggerman in the 1947 hit on Benjamin "Bugsy" Siegel at his Beverly Hills mansion was Robert MacDonald who was contracted for the killing by Los Angeles mob boss Jack Dragna according to researcher Warren Hull as reported by Patrick Healy for NBC 4:
He's just out of control," said Hull, who said relatives knew that MacDonald was abusing drugs and alcohol, and perhaps worse, running up gambling debts to the mob. Dragna knew that during World War II, Army Lt. MacDonald had become an expert marksman with a number of weapons, including the .30 caliber carbine. "Dragna gets him involved. He says, 'Look, here's what's going to happen. Either do this and we wipe the slate clean, or you're going to pay me the $30,000 that you owe me,'" Hull said.
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