Examination of the Decedent and Postmortem Findings
The external examination
The investigator's documented observations form the foundation of the autopsy record. Describe clothing, general appearance, height and weight, identifying features, and medical intervention such as intubation, IV lines, or defibrillator pads. Measure and describe each injury by type, size, shape, location, and color, and photograph with a scale. Distinguish antemortem injury from postmortem artifact: postmortem abrasions are dry and yellow-brown without vital reaction.
Postmortem changes
Livor mortis is the dependent purpling of blood; it blanches early and becomes fixed in roughly 8–12 hours, so a body with fixed lividity in a non-dependent position has been moved. Rigor mortis begins in small muscles within about 1–2 hours, becomes complete near 12 hours, and resolves over the following day. Algor mortis - cooling at roughly 1–1.5 °F per hour under temperate conditions - and decomposition add further information. Each is modified by ambient temperature, clothing, body habitus, and drugs; never estimate time of death from a single finding.
Injury patterns worth naming
Blunt force produces contusions, abrasions, and lacerations with tissue bridging; sharp force produces cleanly divided edges without bridging; gunshot wounds show an entry defect with an abrasion collar and a larger, irregular exit. Defense wounds on the forearms and hands suggest a struggle.
Trap: calling fixed livor a bruise, or assuming the most dramatic injury caused death. Rule of thumb: describe and measure; interpretation belongs to the pathologist.