A teenager was bludgeoned to death the night before Halloween in 1975. A Kennedy cousin was arrested - and then exonerated

Martha Moxley was killed the night before Halloween in 1975. Michael Skakel, a cousin of the Kennedys, spent a decade in prison for her murder, although the conviction was later overturned - (AP)

For nearly 50 years, a quiet, affluent community in Connecticut has been haunted by the unsolved murder of Martha Moxley, a 15-year-old who was bludgeoned to death with a golf club.

It happened on the night before Halloween, known to some as the “Night of Mischief” in which teenagers celebrate the holiday one night early by terrorizing the neighborhood with relatively harmless pranks like egging and toilet-papering houses.