Rain, a Revolver in a Puddle, and a Boot
At 21:40, in steady rain, a 34-year-old man is found in the driver's seat of a sedan on the third level of a public parking garage, with a single gunshot wound to the left chest. Paramedics removed him; the driver's door stands open, the engine is off, the headlights are on. Rain is blowing across the open door. The windshield in front of the driver shows a star-shaped fracture with a bullet hole, the driver's window is shattered out, and there is a hole in the driver's door interior trim. A deformed bullet lies on the passenger seat. A revolver rests in a 5 cm puddle beside the car. The garage manager says the ramp camera records to a DVR that overwrites every 72 hours. Two officers have walked around the car, and one moved the revolver with his boot 'to see if it was real'. No casing is visible.
1. An officer moved the revolver with his boot. How do you handle that, and what does it change for the firearms examination?
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Handle it openly and on the record. Isolate the officer, take a written statement with times, and photograph the boot sole. The boot is now potential evidence: movement can transfer blood, GSR, DNA and trace to it, and it can deposit the officer's own material on the grip. At minimum photograph and swab the sole; consider seizing the boot and recording the tread pattern, because a boot print elsewhere in the garage could otherwise be attributed to the suspect.
For the weapon, the movement and the immersion both matter. Water lifts and redistributes latent print residue and dilutes DNA, but the grip texture, the cylinder flutes, and interior surfaces may still yield something. Tell the examiner about both insults so a negative result is not read as 'never touched'.
Do not unload, cock, dry-fire, or wipe it. Photograph in place, note chamber and cylinder position and whether the hammer is cocked, drain the water, package in paper or a rigid container, and deliver promptly. If transport will exceed a day, discuss with the lab whether to keep it submerged in clean water to limit rust.
2. What can the windshield star fracture and the door-trim hole tell you, and what can they not tell you?
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Windshield: it is laminated, so it holds a star and a hole rather than shattering. The face with the crater and conchoidal flaking is the exit side; the face with the clean, perpendicular edge is the entry side. Photograph both faces with scale and record which is which before any glass is removed.
Door trim: in sheet metal and plastic, the bevel flares on the exit side, and paint flaking and deformation point the same way. On the entry face, look for bullet wipe - the grey lead-and-grease ring - and photograph it before anything touches it. For sequencing, a crack that terminates at another crack is the later one, which can order the impacts.
What they cannot tell you: the shooter's position. That requires the victim's posture at the time of the shot - and paramedics moved him - plus the seat position, the vehicle's exact placement, and a trajectory reconstructed from at least two points. Nor can you assign the bullet on the passenger seat to a specific defect without a laboratory comparison of rifling and weight; a bullet found in the cabin is not automatically the bullet from the door.
3. What are your actions for the DVR and for the casing search?
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DVR: this is a perishable item and it outranks almost everything else. Serve a written preservation request on the manager now, then have him export the interval from roughly 20:00 to 22:30 in native format under your observation, with a hash value and a chain-of-custody entry. Record the DVR clock offset by comparing it against a reliable time source - clock drift routinely decides whether footage is argued to show the right car. Do not let the manager do the export unaccompanied.
Casing: the absence is expected, and that is the reasoning point - a revolver does not eject. Check the cylinder for fired cases and look for a speedloader or loose rounds. Still search the puddle, the floor drain, the wiper cowl, and the interior, because a second weapon or a reload is possible. Use a metal detector plus a hand search along a plausible ejection arc, and remember a wet casing still carries prints and DNA.
Finally, cover the open door against the rain without touching surfaces, and record the time you did it.