Virtually all hangings are suicidal.3
The most common point of suspension is side of the neck, followed by the back and the front. At time of suspension, the noose typically slips above the larynx, catching under chin. Present on the neck will be a furrow. This furrow generally does not completely encircle the neck, but rather slants upwards toward the knot, fading out at the point of suspension the knot. If the knot is under the chin, its site might be indicated by abrasion or indentation beneath the chin. The clarity and configuration of the furrow depend upon the material used. A rope will give a deep, well demarcated, distinct furrow, often with a mirrorimage impression of the twist of the rope on the skin. This furrow initially has a pale yellow parchment appearance with a congested rim. With time, the furrow dries out and becomes dark brown. If the ligature is soft material, the groove might not be properly defined, pale and devoid of bruises and abrasions. In some cases, the margin of the groove is pale, with upper margin red, caused by post mortem congestion of vessels. A towel can give poorly defined superficial areas of abrasion.3
The appearance of ligature mark on the neck is subject to considerable variation,3 depending on the nature of the ligature, the amount of resistance offered by the victim and the amount of force used by assailant.
The geometry of the mark is important in interpreting the fatal events.4 In strangulation, unlike hanging; the mark tends to encircle the neck horizontally and at a lower level. Typically it crosses immediately above or below the prominence of the larynx and passes back to the nape of the neck. In homicide, where a single turn is used, there is often a cross-over point where the two ends of the ligature mark overlap. This may be at front, side or back of the neck, depending on the relative positions of assailant and victim.
The mark on the neck in hanging can almost always be distinguished from ligature strangulation.