Scene Investigation and Scene Documentation
Control before collection
Scene work begins with safety and preservation: PPE, hazard assessment, an entry and exit log, and a perimeter that is widened rather than narrowed. Your first walk-through should be slow and narrative - route, lighting, weather, who is present, what has been moved. Document before you disturb. Medical intervention is the most common source of scene alteration, so capture EMS debris, defibrillator pads, IV lines, and CPR-related injuries as intervention artifacts rather than as evidence of assault.
The documentation triad
Photography, sketch, and notes must each stand alone. Photograph in three scales - overall, midrange, and close-up - with and without a scale, and include the body's relationship to fixed objects. Sketch to scale with measured distances from permanent reference points. Notes should timestamp everything and record ambient temperature, body temperature, and environmental conditions, because these drive later estimates of time since death.
Body and evidence
Record position, clothing, livor distribution and blanching, rigor, and obvious trauma before movement. Photograph the hands before bagging them. Package and seal each item with initials, date, time, and location; every transfer is logged.
Traps
Test questions reward restraint. Do not determine manner from the scene alone, do not label fixed livor as bruising, and do not let a plausible story replace documentation.
Rule of thumb
Photograph before you touch, and write down a time for every action you take.