The shadow home secretary, Chris Grayling has said that a Conservative government will adopt a system used in Scotland to manage and store DNA taken from innocent people arrested in England and Wales.

Mr Grayling told Sarah Montague that "where the DNA in minor cases is destroyed at the end of the inquiry but in more serious cases, life for example a rape inquiry, the police have the ability to retain the DNA for up to five years in order to ensure that they can really see through their inquiries properly.

"What I don't think we should be doing is saying to absolutely everybody who is pulled into a police station for any reason your DNA will be taken and it'll be stored indefinitely as is the case at the moment or indeed will be stored for up to six years as the government appear to be proposing.

"One of the fundamental principles of our criminal justice system is that you are innocent until proven guilty and I think this actually undermines this principle."

Mr Grayling's comments come as the Home Office is set to reveal proposals to retain the DNA of innocent people for a maximum of six years.

This move comes a year after the European Court of Human Rights said the existing indefinite limit was unfair.

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