Secrets of a Homicide: Summary of Conclusions

4. A hypothetical trajectory cone representing possible
trajectories entering JFK's skull at the right-front is
inconsistent with a shot from the grassy knoll.

Some critics of the Warren Report postulate that the bullet that struck the president's head entered at the right front of the skull and exited at the right rear - a trajectory in direct opposition to the findings of both the Warren Commission and the House Select Committee on Assassination's Forensic Pathology Panel. The alleged source of the critic's headshot theory is the "grassy knoll," an elevated area of ground located to the right front of the presidential limousine. A hypothetical trajectory cone was created to test the validity of the critics' claim.

A trajectory cone was created to encompass all hypothetical bullet trajectories entering the right front of JFK's skull and exiting at the lower right. Since the autopsy photographs and x-rays show no damage left of the midline of the president's skull, the cone was positioned to encompass as much of the right frontal area as possible without crossing the midline. This cone was then locked to the model of JFK's skull and applied to the computer recreation. The computer motion model was advanced to the equivalent of Zapruder frame 312 (the last known frame before impact) and the results studied from a variety of angles.
JFK Hypothetical Head Wound Trajectory Cone

JFK Hypothetical Head Wound Trajectory Cone - top/side view A top down view shows the right edge of the trajectory cone lying approximately 1 foot to the right of, and parallel to, the midline of the limousine. The blue area of the cone defines those trajectories not blocked by the windshield of the limousine. A right side view shows the cone intersecting the pavement directly below the front tires of the limousine. The windshield would block a number of angles to the left front of the limousine. A green line drawn between the head wound and the overpass - along the northern edge of the cone, and high enough to clear the windshield - intersects the Triple Overpass at the south curb of Main Street, 13 feet above the top of the overpass. This would be an impossible trajectory under the circumstances.

An aerial view of the scene reveals that the "grassy knoll" (yellow circle) - suspected source of a right-frontal head shot - is outside the area defined by the hypothetical trajectory cone.

The windshield effectively eliminates any firing source within the red cone area, since the green line shows all trajectories clearing the top of the windshield frame track to a source 13 feet above the top of the overpass.

The blue cone area remains the only possible source of a frontal trajectory as described above.
JFK Hypothetical Head Wound Trajectory Cone - aerial view

It should be noted that this is a hypothetical trajectory cone, and does not prove that a shot was fired from this location. On the contrary, this hypothesis is not supported by the available medical evidence. Not a single witness to the assassination suggested that a shot was fired from this area, nor was any physical evidence ever recovered that would support such a claim. In fact, the area described is nearly 180 degrees opposite of the location known as the "grassy knoll" - the long suspected source of the headshot.

In conclusion, the hypothesis that a bullet fired from the "grassy knoll" struck the president in the right-front of the skull and exited at the right-rear, is invalid.


Secrets of a Homicide: JFK Assassination © 1995-2008 Dale K. Myers. All Rights Reserved.
Published by Oak Cliff Press, Inc., P.O. Box 608, Milford, MI 48381-0608