(SAN FRANCISCO CHRONICLE) — There were no witnesses, no fingerprints, no gun and little forensic evidence when a woman was found slain 26 years ago. But there was a human bite mark on her arm — a bite that came back to haunt a female police detective who was unmasked as the killer of her former lover’s wife.

Stephanie Lazarus, trained in police procedures, knew enough to cover her tracks, prosecutors said, but could not have guessed in 1986 that the bite would be analyzed by a tool known as DNA testing, which was in its infancy then.

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