Kirk Bloodsworth was convicted of the rape and murder of nine-year-old girl Dawn Hamilton in Maryland in 1984 and sentenced to death.

While in prison he read a book on DNA fingerprinting which spurred him on to persuade his lawyer to petition for evidence against him to be DNA tested.

Here he talks to Newsnight about the moment that he found he had been cleared and of his great admiration for the man who invented DNA profiling, Professor Sir Alec Jeffreys.

Watch the Newsnight film on 25 years of DNA fingerprinting on Wednesday 9 September 2009 at 10.30pm on BBC Two.