Ann Rule was a popular American true crime writer. Raised in a law enforcement and criminal justice system environment, she grew up wanting to work in law enforcement herself. She was a former Seattle Policewoman and was well educated in psychology and criminology.

She came to prominence with her first book, The Stranger Beside Me, about the Ted Bundy murders. At the time she started researching the book, the murders were still unsolved. In the course of time, it became clear that the killer was Bundy, her friend and her colleague as a trained volunteer on the suicide hotline at the Seattle, Washington Crisis Clinic, giving her a unique distinction among true crime writers.

Rule won two Anthony Awards from Bouchercon, the mystery fans' organization. She was nominated three times for the Edgar Awards from the Mystery Writers of America. She is highly regarded for creating the true crime genre as it exists today.

Ann Rule also wrote under the name Andy Stack . Her daughter is Goodreads author Leslie Rule.