PITTSBURGH (NewsRadio 1020 KDKA) – A veteran police detective in Melbourne, Australia believes that after four years of continuous research and writing, he has uncovered just how President John F. Kennedy was killed.

Colin McLaren used the research from another author to inspire his ongoing investigation in to the truth.

McLaren built his book, “JFK: The Smoking Gun,” around the research previously done by ballistics expert, Howard Donahue.

Donahue spent 20 years studying the JFK assassination and his work is included in author Bonar Menninger’s book, “Mortal Error: The Shot that Killed JFK.

His fascination started when he was on vacation many years ago and came across Menninger’s book. Then for the next 15 years his interest was peaked and he wanted to know more about the information that Donahue and Menninger had presented.

McLaren started his research in January of 2009. His work is a confirmation of Donahue’s theory and a continuation of Menninger’s research.

To summarize their theory of the accident, a Secret Service agent accidentally fired that fatal shot. There were three rounds, but the third came from a different place causing President John F. Kennedy’s head to move forward, not behind.

There were two guns, three bullets and two shooters. One was using a full metal jacket bullet that was fired twice at the president, then a hollow-point bullet fired from a rifle to kill him.

So the story goes, a Secret Service agent in the car behind the president’s was standing on an unstable vehicle and stumbled over, accidentally pulling the trigger and firing at the president.

“This was clearly a horrific accident with a fool-hearted, poor assassination attempt by Lee Harvey Oswald,” said McLaren.

“If you look at the science of it all it has to be from behind and it has to be a straight level and it has to be from somebody with a .223 or hollow-point round, that’s a rifle round,” said McLaren. “And who on that day was armed with a round or at least a rifle firing a hollow-point, the question is easy to answer, it’s the Secret Service detail in the car behind.”

He examined the characters of the Secret Service men who later admitted to drinking alcohol and entertaining strippers the night before. McLaren feels that these men were hung over, with clouded minds while wearing impaired dark sunglasses.

Although, he believes the agent who accidentally fired his gun was a new member to the team and was strictly assigned as the driver not a field agent.

Witnesses who were there say that they saw the men in the second car falter and stumble in the chaos and panic. This was an event that could never be replicated and is a “once in history” moment.

On Nov. 3 the REELZ channel will broadcast the documentary “JFK: The Smoking Gun.”