There was someone firing from the grassy knoll.
That, at least is the finding, 39 years later, of a new scientific study of the evidence on the assassination of President John F. Kennedy, evidence which confirms the finding 22 years ago by the House Assassinations Committee that the murder in Dallas "was probably the result of a conspiracy".
An article in the respectedScience and Justice, the journal of the British Forensic Science Society, by Dr D.B. Thomas argues that there is a 96 per cent chance that there was a shot from the grassy knoll to the right of the president's limousine in addition to the three fired from the Texas Book Depository by Lee Harvey Oswald.
Dr Thomas, a government scientist and JFK assassination researcher, argues that the shot was the one that killed Kennedy.
The Thomas study involves a review of the evidence examined by a panel established by the National Academy of Sciences (NAS) in the wake of the House committee's findings.
The NAS had dismissed the muffled sound heard on a Dallas police HQ tape of an open police radio call and believed to be the fourth shot as a random piece of static, recorded perhaps a minute after the killing.
The NAS had also dismissed as static the three Oswald shots, despite the fact that the House research had been able to tie them to the time of the shooting.
But, according to Dr Thomas, the NAS, in using a second recording as a timing reference, had mistakenly displaced the grassy knoll shot by a minute.
Using common recordings of cross-talk by a local police sergeant the alleged fourth shot, he says, is found to coincide exactly with the killing.
In its investigations, now substantially validated, the House researchers were able to place a gunman behind a picket fence on the knoll above, in front of and to the right of the presidential limousine, by a careful testing of the echo patterns produced by the shot.
Mr G. Robert Blakey, former chief counsel to the House Assassinations Committee, has always been concerned by the NAS study because they had dismissed all four shots as just random noise despite the fact that three of them coincided exactly with evidence from film of the assassination.
He told the Washington Post that he welcomed the Thomas re-examination of the evidence. "This is an honest, careful examination of everything we did with all the appropriate statistical checks," he said.
"It shows that we made mistakes, too, but minor mistakes. The main thing is that when push comes to shove, he increased the degree of certainty that the shot from the grassy knoll was real, not static. We thought there was a 95 per cent chance. He puts it at 96.3 per cent. Either way that's `beyond a reasonable doubt'."