El Cajon, Calif. resident Thomas Pendergast was driving on the San Diego Freeway in the fall of 1958 when cops say he noticed a hitchhiker on the side of the road.
Thomas offered the 16-year-old a ride and later decided to invite the homeless teen home.
El Cajon cops say that six weeks later, hitchhiker -- Carl Alfred Eder -- was arrested for murdering Thomas' wife and four children.
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