What forensic disagreements exist about the number of shooters and bullet trajectories at Dealey Plaza?
Executive summary
Forensic debate over Dealey Plaza centers on two linked disputes: whether one shooter (Lee Harvey Oswald from the Texas School Book Depository) fired all fatal rounds, and how bullet paths—most notably the “single‑bullet” trajectory and the alleged frontal shot from the Grassy Knoll—can be reconciled with wounds, film, photographs and physical traces; official reconstructions support a lone shooter and back‑to‑front fatal trajectory while modern re‑scans and dissenting analyses argue some trajectories are inconsistent or point to a second shooter [1] [2] [3] [4].
1. The Warren Commission and later panels: single‑shooter, plotted trajectories
The Warren Commission and later investigations used forensic pathology, ballistics and frame‑by‑frame photographic analysis to plot trajectories that point back to the sixth‑floor window of the Texas School Book Depository and concluded Oswald fired three shots with two striking the President and Governor Connally, a finding the House Select Committee on Assassinations (HSCA) and National Archives summaries echoed in describing separately developed direction and slope trajectories for the bullets [1] [2].
2. The single‑bullet theory: technical success, public doubt
Arlen Specter’s reenactment replicated the so‑called single‑bullet path connecting wounds to Kennedy and Connally and remains a cornerstone of the lone‑gunman narrative, yet the theory has long been contested because it requires a complex through‑and‑through path and alignment of occupants that some forensic skeptics say strains plausibility despite official reconstructions asserting consistency with wounds and Zapruder frames [2] [1].
3. Grassy Knoll proponents: eyewitnesses, acoustic hints and the windshield hole
Researchers advocating multiple shooters point to eyewitness reports favoring sounds from the Grassy Knoll, the observation of a windshield hole and forensic work alleging a frontal shot that doctors at Parkland observed; the HSCA’s acoustical team initially reported an apparent second‑shooter probability, and conspiracy supporters cite these cues as evidence of crossfire from the knoll [3] [5] [2].
4. Acoustic and psychoacoustic limits: why human perception misleads
Countering earwitness claims, psychoacoustics research emphasizes that supersonic bullet shock waves and reverberation in Dealey Plaza can mislead listeners about origin—shock waves reveal the path, not the source, so conflicting testimonies are scientifically plausible without requiring a second shooter, an important corrective raised by modern acoustic and perceptual studies [6].
5. Modern reconstructions and renewed disputes: lasers, 3D models, and contradictory results
Recent high‑definition laser scans and digital twins—such as work by Leica‑assisted teams and Knott Laboratory—have been used to remeasure angles and timing; proponents report that precise point clouds still permit all three shots to be fired from the Depository within the timeline and can reproduce the single‑bullet path, while other new analyses claim some measured trajectories are incompatible with the Warren geometry and therefore resurrect doubts about additional shooters or unexplained impacts [7] [4] [8].
6. Where the forensics disagree and why it persists
Disagreement concentrates on a handful of contested data points—the validity of the single‑bullet through‑and‑through trajectory, the interpretation of the Zapruder frames and photographic evidence, the forensic meaning of the windshield impact and curb‑chip (Tague) and the weight to be given to acoustic analyses versus pathology and ballistics; moreover, entrenched narratives and advocacy groups on both sides selectively emphasize data that feed their thesis, so forensic claims are often presented with implicit agendas—either to close the case for a lone gunman or to substantiate a conspiracy—which keeps the debate alive despite repeated technical reexaminations [1] [9] [10] [3].
7. What the sources cannot settle here
Available reporting and reconstructed models demonstrate persistent ambiguities but do not provide a single conclusive new dataset that unambiguously overturns the official trajectories or proves an additional shooter beyond reasonable doubt; where assertions exceed cited reconstructions, the public record as sampled here stops short of a definitive forensic resolution and therefore leaves the principal disagreements—number of shooters and precise bullet paths—open to interpretation within the limits of existing evidence [4] [8] [3].