Coroner Veronica Hamilton-Deeley recorded a verdict of ‘accidental death’ in the case.
Evidence established the teenager died of multiple brain injuries.
Testimony indicated 15-year-old Arthur Cave had taken the hallucinogenic LSD with a friend shortly before the fall that ended his life.
He was spotted by motorists who saw him ‘staggering’ and ‘zig-zagging’ on top of the cliff near Brighton in East Sussex – after taking the substance.
While having ‘vivid hallucinations’ he had clambered over a fence put in place to keep the public away from the 18-metre drop and was walking alone across a patch of grass with less than a metre of ground ahead of him – a coroner was told.