Defense Forensic Summary
State of Utah v. Tyler Robinson — Preliminary Hearing May 18, 2026
Eleven independent recordings. Five acoustic signatures. Three spatially separated sources.
Section 01 — The Official Narrative
Tyler Robinson fired a .30-06 rifle from approximately 127 meters (139 yards), striking Charlie Kirk in the neck. A single shooter, a single event, a single source.
If this theory is correct, the physical evidence must show:
None of these predictions hold. Audio arrives within 0–2 frames. Motion is radial, not directional. Multiple acoustic sources at multiple locations are detected. And a detonation signature is isolated at the stage — spectrally distinct from the rifle.
Section 02 — The Centerpiece Evidence
A professional broadcast camera was recording at UVU — 4-channel 48kHz uncompressed PCM audio. No lossy compression. No codec artifacts. No temporal smearing. Phone recordings are like looking through a foggy window. The Canon XA55 is a clean window with the lights on.
The Canon resolves three separate low-frequency events that every phone recording blurs into a single noise. For the first time, we can hear the rifle and the stage detonation as two distinct events.
Timing reference: All three offsets below are measured from the moment the Mach cone (supersonic crack) reaches the Canon's microphones. This is the standard "crack-to-blast" reference used in forensic ballistics.
The stage detonation is spectrally distinct from the muzzle blast — 656Hz centroid vs 2,429Hz. A rifle 120 meters away and a detonation at the tent are two different events at two different locations. A single-source theory cannot explain this.
Section 03 — Reconstructed Timeline
Geometric reconstruction from GPS-verified positions: rifle at 127m from tent, 120m from Canon; Canon at 46m from tent. Triangle angle at Canon: 88° — the Canon sees the rifle and the tent at nearly perpendicular directions, which is why it resolves them as separate events.
The stage detonation occurs 191ms after the bullet arrives at the tent. The electronics chain (mic → ARM processor → detonator) fires in under 10ms.
The remaining ~180ms is consistent with:
• LiPo thermal runaway cascade (150–500ms published range)
• Intentional firmware delay after N-wave detection
• Pyrotechnic delay element (standard in ordnance)
335ms (detonation time) + 134ms (sound travel tent → Canon) = 469ms arrival at Canon.
148ms (Mach cone at Canon) + 321ms (measured delay) = 469ms. Exact match.
Section 04 — Supersonic Evidence
A supersonic bullet creates N-wave pressure signatures — rapid zero-crossings in the audio. The Canon's uncompressed format preserves what phone codecs destroy.
| Recording | Sub-200µs ZCs | Fastest |
|---|---|---|
| Canon CH1 (Shotgun) | 765 | 20.8µs |
| Canon CH3 (Built-in) | 518 | 20.8µs |
| 7.mp4 (best phone) | 123 | 22.7µs |
| IMG_6368 (phone) | 2 | 90.7µs |
Both Canon channels hit the 20.8µs Nyquist floor — supersonic content exceeds even professional recording bandwidth.
High frequencies arrive first (+0ms), low frequencies last (+103ms). This is the diagnostic signature of a supersonic event followed by a delayed blast wave — not a single detonation, which would arrive simultaneously across all bands.
122,844 clipped samples on the directional shotgun mic. Zero correlation with the built-in mics. The event source was on-axis with the shotgun's pointing direction — toward the stage.
Section 05 — Supporting Evidence
Light travels instantly. Sound at 343 m/s. The gap between the visible event and the audio arrival — measured within each camera's own synchronized track — gives the distance to the source. No cross-camera sync required.
Open any source video in VLC. Press 'E' to step one frame at a time. Find where the shirt begins to expand. Find where the audio spike hits. Count the frames. At 127 meters (the prosecution's distance), you should count ~11 frames. You won't. The audio-visual delay is consistent with a source at the body — not 127 meters away.
Section 06 — The Detonation Thesis
The acoustic, visual, and physical evidence converges on a single conclusion: an energetic detonation occurred at the RØDE Wireless PRO transmitter location on Charlie Kirk's chest. This detonation — not a distant rifle impact — explains every physical observation.
The acoustic rise time of the stage event is 104 microseconds. LiPo thermal runaway produces 1–10ms rise times. Chemical detonation (PETN) produces sub-millisecond rise times. The measured 104µs favors detonation over natural battery failure by an order of magnitude.
Section 07 — Physical Evidence
Dense optical flow, frame differencing, and divergence analysis all converge on a single epicenter: pixel coordinates (775, 562) — the exact location of the RØDE Wireless PRO transmitter on Charlie Kirk's chest.
The metal necklace snaps and launches upward at 21+ m/s (47+ mph) — requiring a minimum of 6.8 joules of kinetic energy. The trajectory launches upward and outward from the transmitter location. A .30-06 bullet traveling horizontally would drive material inward and downward along its trajectory — not upward perpendicular to it.
In the first frames of shirt movement, debris is visible flying away from Charlie Kirk. The RØDE circuit board (30×28mm, blue solder mask) is tracked across six stages: housing breach → chest transit → collar capture → descent inside shirt. Colorimetric analysis confirms the blue PCB solder mask (B/R ratio 0.567 vs skin 0.546). The housing bulge is absent post-event.
Section 08 — Medical Evidence
Decorticate posturing — involuntary arm flexion indicating severe brain stem disruption — appears within frames of the initial deformation, approximately 0.4 seconds before the neck wound becomes visible.
If a rifle bullet struck the neck, neurological response would follow the wound. Instead, decorticate posturing precedes visible bleeding by ~0.4 seconds. Brain injury occurred via a different mechanism — one that did not require external penetration of the neck.
Acoustic analysis detects peaks at 53Hz, 80Hz, and 133Hz — matching published chest wall structural modes and Helmholtz lung cavity resonance. Audio evidence of chest cavity penetration.
A detonation at the RØDE transmitter location could drive shrapnel into the thoracic cavity. Chest penetration causing pneumothorax or direct thoracic nerve disruption would explain both the 53Hz resonance and the early decorticate posturing — brain trauma from thoracic shock, not a neck entry wound.
Section 09 — Acoustic Fingerprint
Each signature localizes to a different spatial origin via independent TDOA multilateration:
Timing reference: relative to Mach cone arrival at the nearest camera to each source.
| Signature | Frequency | Timing | Source Location |
|---|---|---|---|
| Mach Cone | 500Hz–8kHz (centroid 2,755Hz) | t = 0ms (reference) | Rooftop — 127m from tent |
| RØDE Detonation | 200Hz–6kHz (centroid 1,562Hz) | +191ms at source | Tent — on victim's chest |
| Chest Cavity Resonance | 53Hz, 80Hz, 133Hz | 100–200ms decay | Victim's thorax |
| Muzzle Blast | 30Hz–500Hz (centroid 2,429Hz) | +233ms crack-to-blast at tent | Rooftop — 127m from tent |
| 4940Hz Strouhal Tone | 4,700–5,200Hz | +0.5ms after Mach | Van — 3.3m from walkway |
A single device malfunction at the tent cannot produce a Mach cone from a rooftop 127 meters away. A single rifle shot cannot produce a detonation at the tent with a 656Hz spectral centroid. A single event at any location cannot produce a 4940Hz tone originating 3.3 meters from a parked van. Five distinct signatures from at least three spatially separated locations.
Section 10 — Unified Theory
Six independent lines of physical evidence, each predicted by the detonation thesis, each contradicted by a single-rifle-shot theory:
Radial gas-driven expansion from the RØDE location. Gas visible one frame before mechanical deformation. Consistent with internal pressurization — not external impact.
21 m/s upward launch, 6.8J minimum energy, trajectory perpendicular to any rifle vector. Consistent with radial blast centered at the transmitter.
Debris flies outward from Charlie in the first frames. Circuit board tracked across chest, into collar, down inside shirt. Housing absent post-event.
Optical flow converges on (775, 562) — the RØDE transmitter. 4× peak motion. Radial pattern = internal source, not directional impact.
Audio evidence of chest cavity penetration. Chest wall structural modes at 53/80/133Hz detected acoustically. Explains thoracic trauma pathway.
Brain trauma appears ~0.4s before neck bleeding. Consistent with thoracic shock from chest detonation — not a neck entry wound.
Conclusion
Eleven independent recordings. Five distinct acoustic signatures from three spatially separated locations. A detonation at the tent spectrally distinct from the rifle. Audio-visual delay of 0–2 frames, not 11. Radial motion from the transmitter location. Shrapnel flying outward. A necklace launched upward at 47 mph. Brain trauma before the wound. And a 53Hz signal that says something penetrated the chest.
Reasonable doubt does not require proving what happened. It requires showing that the prosecution's theory — a single rifle shot from 127 meters — cannot account for the physical evidence. It cannot.
Supporting Documents
Interactive 4-channel audio analysis with raw source audio downloads.
View Analysis