DNA “Fingerprints” are forever:

A man has admitted raping an 18-year-old woman who was walking her dog on a footpath more than 30 years ago.
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The case featured on the BBC’s Crimewatch programme in 2008, but despite a huge number of calls from the public, no one was ever charged.

Shakespeare was caught after a DNA sample was taken by police after he was arrested for exposing himself to a woman in a park, which matched the profile of the attacker on the national database.

Judge Ian Lawrie said it was “extraordinary” the DNA evidence was still available to prove Shakespeare’s guilt after such a long time.

“I didn’t realise you kept DNA banks that long,” he told the court.

https://www.bbc.co.uk/news/uk-england-59333961