Geneticist Alec Jeffreys developed DNA fingerprinting at the University of Leicester, England, in September 1984, discovering that segments of DNA contained repeating sequences unique to each individual. He quickly recognised the forensic potential of the technique for criminal identification and paternity testing. Within two years, DNA profiling was used in a criminal investigation for the first time, and by 1986 it had both exonerated an innocent suspect and led to the conviction of Colin Pitchfork in Leicestershire — the first criminal caught using DNA evidence.

DNA fingerprinting was arguably the most significant advance in forensic evidence gathering since the adoption of fingerprints, and it reshaped crime fiction, popular culture, and public understanding of identity and individuality. The idea that a person's body carries irrefutable evidence of their presence entered literary consciousness immediately and has been a major theme in crime fiction and science writing since the 1980s. The technique also proved central to the innocence project movement, generating powerful narratives of wrongful conviction.