Referring to John McAdams, "a good many of the deaths hardly seem mysterious in that they were caused by accidents, heart attacks, and other phenomena that afflict our entire population."
However, when one reads Richard Charnin's 2013 column, the probability of death of 7 current or former FBI officials who died during a six-month period in 1977 before they were to testify before the House Select Committee on Assassinations when calculated using Probability Sensitivity Analysis was approximately 1 in 100 billion.
The List of Witnesses and Cause of Death
All these witnesses were to testify, had already testified, or were to be called back for additional testimony. Their deaths with no indication of foul play however cluster about a very specific period of curious time of the hearings before the Senate Intelligence Committee and HSCA.
William Sullivan-the main figure in the FBI involved in the
Executive Action project was shot dead in a shooting accident near
his home in Sugar Hill, New Hampshire, on 9th November, 1977 a week
before he was to testify before the House Select Committee on
Assassinations in 1977. Investigation by New Hampshire authorities
showed no indication of foul play.
William Sullivan was one of the former FBI director J. Edgar
Hoover’s top aides, originally, then had a falling out with Hoover.
He was scheduled to be questioned by the Assassinations Committee in 1977. As mentioned earlier, he was found shot dead in a shooting accident having been mistaken for a deer. He had been head of the
FBI’s Division Five, which handled the King and Kennedy
investigations. There was a claim by William Sullivan's friend
Robart Novak that William Sullivan specifically predicted that his
own death by the following words "Someday you will read that I have
been killed in an accident, but don’t believe it; I’ve been
murdered."
Donald Kaylor-One of hundreds of FBI employees with marginal connection to assassination who died in October, 1977. He was a FBI fingerprint chemist who examined prints found at the assassination scene and the cause of death was from heart attack.
J.M. English-former head of FBI Forensic Sciences Laboratory died in October, 1977 from heart attack with no evidence of foul play.
Alan H. Belmont-special assistant to Hoover died in August, 1977 from natural causes due to "long illness" with no evidence of foul play. He had previously testified to the Warren Commission.
James Cadigan-FBI document expert with access to documents that related to death of John F. Kennedy died from a fall in his home in August, 1977 with no evidence of foul play. He had previously testified to the Warren Commission.
Louis Nicholas-special assistant to J. Edgar Hoover and his liaison with the Warren Commission died from heart attack in June, 1977 with no evidence of foul play. He was a Former No. 3 man in FBI who worked on JFK assassination investigation.
Additional deaths during the interview period: Apart from the above listed agents, Regis Kennedy who was a senior agent in the FBI assigned to New Orleans also died during the HSCA interview period. He was one of two FBI agents in New Orleans assigned as contact men for Lee Harvey Oswald in his role as FBI informer. Regis Kennedy’s death would be considered curious, not suspicious, due to the coincidence with his HSCA interview per Jerome A. Kroth. He informed the Assassinations Committee in 1978 that Carlos Marcello, the alleged Mafia boss in New Orleans, was not affiliated to organized crime and was a tomato salesman. Regis Kennedy died shortly after testifying before the Committee in 1978. Kennedy is said to have confiscated a film of the assassination taken by what conspiracy researchers call “The Babushka lady film” which was seized before anyone ever viewed it, and was never recovered.