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Electrical and lightning deaths — the forensic findings

Death from low-voltage current is usually caused by an arrhythmia (ventricular fibrillation) and may leave only a small electrical mark at the point of contact — or no mark at all, especially when the skin is wet — whereas high voltage and lightning cause extensive burns, arcing and distinctive findings; the diagnosis therefore relies on the scene and on examining the installation as much as on the body.

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Why it matters in the exam

The exam asks what the electrical mark looks like, when it is absent and what characterises lightning. The low-voltage electrical mark (Joule burn) is a small firm grey-white lesion with raised pale margins and a central depression, usually on the palm or fingers that touched the source; sometimes there is an exit mark on the foot. Microscopically there are elongated, parallel-aligned nuclei in the basal layer (nuclear streaming) and vacuoles in the epidermis, but these are not specific to electricity. When the skin is wet, for example in a bath, resistance is low and the current passes over a wide area — so death without any mark is possible.

With high voltage the current can jump through air as an arc and injure without direct contact, resulting in deep extensive burns, metal particles on the skin (metallisation) and muscle and kidney damage. Lightning produces fern-like patterns on the skin (Lichtenberg figures) that appear shortly after the strike and fade within hours to a day, so they are seen in a living victim or a fresh body but not later; there are also burns around metal objects, torn clothing and magnetised metal. When a body is found with a severe burn on one hand and no other findings, the appliance and installation at the scene must be examined.

The conducted electrical weapon (Taser) is examined as a question of proven risk: the established risks are injury from the probes, especially to the eye, and injuries from falling when the person loses muscle control; the link to fatal arrhythmia is debated and judged case by case, often with stimulant intoxication and struggle. In every electrical death the diagnosis includes examination of the installation by an electrical expert, because findings on the body may be minimal.

Key points

• Low voltage: ventricular fibrillation and a small firm electrical mark.
• Wet skin: sometimes death without a mark.
• High voltage: arcing, extensive burns and metal particles.
• Lightning: transient fern patterns and magnetised metal.
• Examining the installation at the scene is part of the diagnosis.

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Sources

• Knight's Forensic Pathology, 4th edition (2016) — Electrical fatalities
• Spitz and Fisher's Medicolegal Investigation of Death, 5th edition (2020) — Electrical injuries and lightning
• Simpson's Forensic Medicine, 14th edition (2020) — Electrical injury

Sources are given for further reading; the text is written afresh and not copied from them.

Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.