Boston mobster "Cadillac" Frank Salemme is on trial for his alleged participation in the murder of Steven DiSarro. Another casualty of Salemme’s was a State Trooper.

Trooper Mark Charbonnier was murdered on September 2, 1994 in the early morning hours during a traffic stop on Route 3 in Plymouth. He shot it out with his killer, and managed to wound him in the head and arm before he died from a bullet wound to his abdomen. His killer, David Clark, was captured at the scene, survived his wounds, and was convicted of killing the trooper.

But who was David Clark, and why would he shoot a police officer on the side of the highway?

David Clark was an associate of Frank Salemme, and law enforcement and mafia experts believe he shot Charbonnier because he had just done some work for his boss. According to court documents, the van Clark was driving that night contained a gym bag with an additional pistol, two ski masks, and a police badge. Clark told police repeatedly he was alone in the van, but there were two guns and two masks in that van with him. Court records also state “defendant previously had vowed never to be returned to prison.”

Given Clark’s knowledge of the criminal justice system and the soft-on-crime judges in Massachusetts, it is difficult to believe he was worried about being caught with a couple of illegal guns. It is hard to see him committing a murder to avoid a year or two in jail if he was found guilty.

What he was concerned with was a murder that had taken place in the Boston area a few hours earlier. The New England branch of La Cosa Nostra was in a bloody internal war, and people were being murdered and disappearing forever. The fight was over control of the lucrative rackets all over Rhode Island, Massachusetts, and parts of Connecticut.

That evening, an innocent young man had been mistaken for a mobster and murdered just outside of Boston, allegedly by Mark Rossetti, a ruthless member of Salemme’s inner circle. Michael Romano was thought to be Enrico Ponzo, who was a rival gangster to Salemme, when he was allegedly murdered by Rossetti.

Award-winning investigative journalist and organized crime expert Michele McPhee explains Clark’s activities in a 2013 story for ABC News. “After the Romano hit in 1994, [Rossetti’s] sidekick David Clark shot and killed Massachusetts State Trooper Mark Charbonnier, according to South Boston Congressman Stephen Lynch and state prosecutors," she wrote.

If Clark hadn’t been out doing work for Frank Salemme that evening, Trooper Mark Charbonnier would be alive today. Salemme didn’t pull the trigger or actually strangle DiSarro, but they are both still dead and it is because of Salemme...allegedly.

Chris McCarthy is the host of The Chris McCarthy Show on 1420 WBSM New Bedford. He can be heard weekdays from 10 a.m. to noon. Contact him at chris.mccarthy@townsquaremedia.com and follow him on Twitter @Chris_topher_Mc. The opinions expressed in this commentary are solely those of the author.