John and Sally Sweek, a young married couple living in east Dallas, were known by friends—a lively party crowd—to sell cocaine out of their apartment. Two of those friends found their bodies there in 1987: The Sweeks had been stabbed to death.
The bloody crime scene was teeming with what investigators considered to be excellent forensic evidence. John appeared to have a bite mark on his left forearm. Sally had hair under her fingernails, presumably from fighting off her attacker. There were two pairs of bloody shoe prints.
Police initially suspected a gang member, then a tip led them to Steven Mark Chaney, a friend who owed the Sweeks $500. It turned out the couple often sold drugs to friends on credit.
