In Scotland, police must destroy the DNA records of suspects who are not convicted, except where criminal proceedings were raised against them for a sexual or violent offence.

However, in light of the increasingly important role DNA plays in detecting crime - for example, DNA evidence was crucial to convicting Peter Tobin this week of murdering the Falkirk schoolgirl Vicky Hamilton - some now favour changing the system

Earlier this year Stephen House, Chief Constable of Strathclyde Police, the country’s biggest force, suggested that he would be in favour of extending the country's database, subject to public debate. He recommended that Scotland implement the English model of retaining the DNA of all suspects as a first step towards growing the number of samples on file.

To address the growing debate over storing DNA, the Scottish government commissioned a DNA review from James Fraser, head of the University of Strathclyde’s Centre for Forensic Science.

However, the Scottish National Party (SNP) is known to be cool on the idea of storing samples from innocent people.

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