Roy Kellerman was born in 1916. After graduating from High School in 1933 he found work with the Dodge Corporation. He left in 1937 to join the Michigan State Police. He served in the force for the next four years.
Kellerman joined the Secret Service in Detroit in December 1941. The following year he was transferred to the office in Washington. In March 1942, he was assigned to the White House. For the next three years Kellerman helped protect President Franklin D. Roosevelt and his family. Later he worked for Harry S. Truman, Dwight Eisenhower, and John F. Kennedy. In October 1962 Kellerman was promoted and given the title of assistant special agent in charge of security.
On 4th November Kellerman was asked to prepare for the presidential trip to Dallas, Texas. This involved discussions with Kenneth O'Donnell (special assistant to Kennedy), Winston G. Lawson (secret service agent in charge of the trip) and Jesse Curry (chief of police in Dallas).
On the 22nd November, 1963, Kellerman accompanied John F. Kennedy in the presidential car in the motorcade through Dallas. The car was driven by William Greer. Kellerman later told the Warren Commission that Kenneth O'Donnell made the decision to remove the bubbletop on the President's car on the way to the Trade Mart.
Several witnesses said that William Greer stopped the car after the first shot was fired. This included Jean Hill, who was the closest witness to the car when Kennedy was hot: According to Hill "the motorcade came to almost a halt at the time the shots rang out". James Chaney (one of the four Presidential motorcyclists) - stated that the limousine "after the shooting, from the time the first shot rang out, the car stopped completely, pulled to the left and stopped." Mary Woodward, a journalist with the Dallas Morning News wrote: "Instead of speeding up the car, the car came to a halt... after the first shot".
Kenneth O'Donnell (special assistant to Kennedy), who was riding in the motorcade, later wrote: "If the Secret Service men in the front had reacted quicker to the first two shots at the President's car, if the driver had stepped on the gas before instead of after the fatal third shot was fired, would President Kennedy be alive today? He added "Greer had been remorseful all day, feeling that he could have saved President Kennedy's life by swerving the car or speeding suddenly after the first shots."
Senator Ralph Yarborough, who was riding with Lyndon B. Johnson, was highly critical of the actions of William Greer: "When the noise of the shot was heard, the motorcade slowed to what seemed to me a complete stop... After the third shot was fired, but only after the third shot was fired, the cavalcade speeded up, gained speed rapidly, and roared away to the Parkland Hospital... The cars all stopped... 'I don't want to hurt anyone's feelings but for the protection of future Presidents, they (the Secret Service) should be trained to take off when a shot is fired."
It has been estimated that 59 witnesses and the Zapruder Film indicated that Greer stopped after the first shot was fired. However, when interviewed by the Warren Commission, Greer claimed: "I heard this noise. And I thought that is what it was. And then I heard it again. And I glanced over my shoulder. And I saw Governor Connally like he was starting to fall. Then I realized there was something wrong. I tramped on the accelerator, and at the same time Mr. Kellerman said to me, "Get out of here fast." And I cannot remember even the other shots or noises that was. I cannot quite remember any more. I did not see anything happen behind me any more, because I was occupied with getting away."
William Greer, Winston G. Lawson and Kellerman denied that the presidential car stopped. In his evidence to the Warren Commission Kellerman claimed that after hearing the first shot he said to Greer, "Let's get out of here; we are hit." He went on to say in a reply to a question by Gerald Ford that Greer's response was immediate: "I have driven that car many times, and I never cease to be amazed even to this day with the weight of the automobile plus the power that is under the hood; we just literally jumped out of the God - damn road."
However, Kellerman did provided evidence that suggested that more than three shots were fired at President John F. Kennedy. He told the Warren Commission that after the first shot was fired "a flurry of shells come into the car". He also claimed that he had seen film that argued against the idea of a lone gunman. However, it appeared that members of the Warren Commission did not want to hear about this and the questioning quickly moved on to another topic.
Later it emerged that both Kellerman and Greer believed that Kennedy had been a victim of a conspiracy. Kellerman's daughter told Harold Weisberg in the 1970's that "I hope the day will come when these men (Kellerman and Greer) will be able to say what they've told their families". After Roy Kellerman's death, his widow reported that her husband was convinced that there had been a conspiracy to kill Kennedy.