SANTA ROSA (CBS SF) — The case of a Colorado man charged with killing three men during a marijuana transaction in Sonoma County three years ago is about betrayal of trust, deceit, and murder, a Sonoma County prosecutor said in his closing statement to the jury.

“This murder was an inside job,” Sonoma County Chief Deputy District Attorney Spencer Brady said.

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The victims “were literally on their knees processing marijuana” when each of them was shot once in the head, Brady said.

According to Brady, 49-year-old Mark William Cappello,  of Central City, Colorado, killed his business partners in a Forestville cabin on Feb. 5, 2013, because the deal was not as lucrative as he expected, and Cappello was in financial dire straits.

One of the victims, Raleigh Butler, 26, of Truckee, who brokered the deal for $8,600, could only come up with 100 pounds of marijuana at best.  There was an expectation the deal involved as much as 1,500 pounds and could be worth $260,000 if it was sold in New York City.

Butler, Todd Klarkowski, 42, of Boulder, Colorado and Richard Lewin, 46, of Huntington, New York, were killed as they packaged the marijuana for transport by two men Cappello hired, Odin Dwyer, 41, and his father Francis, 68.

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Odin Dwyer, of Denver, was in the cabin Butler’s mother owned, and he testified Cappello told him the slayings “had to be done.”

Francis Dwyer, of Truth or Consequences, New Mexico, was in a Santa Rosa motel with Cappello’s dog when the slaying occurred, according to the testimony they gave in return for lighter charges and sentences.

Cappello and Odin Dwyer left the cabin with 69 pounds of marijuana, and he and the Dwyers and returned to Colorado in two separate vehicles. Sonoma County sheriff’s deputies found about 18 more pounds of  processed marijuana in the cabin, according to trial testimony.

Brady also characterized Cappello as an expert at avoiding detection and transporting marijuana, a sharp shooter, counter surveillant and an intimidator who needs to be in control of a situation.

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