Lynn Penn

Lynn Penn, a 60-year-old man, was found strangled inside his apartment in the Westlake area of Los Angeles in July 1990. The killing offered investigators few immediate answers, and the case remained unsolved for more than two decades. Among the evidence recovered from Penn's apartment was a cigarette butt. Although it could not identify his killer at the time, saliva left on that cigarette eventually became the crucial piece of evidence that would reveal who had been inside the apartment.
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