Tory MP Damian Green was arrested last year as part of a Home Office leak inquiry but never charged. He told BBC News that police have agreed to delete DNA, fingerprints and his police national computer record.

"[The decision is] a small but significant victory for freedom and privacy in this country - but what is really important now is that I don't get special treatment just because I am a public figure," he said.

Findlay, director of the Institute of Criminology at the University of Sydney, said the laws vary from state to state in Australia but in NSW a database is maintained, regardless of whether a person is convicted or not.

"What is argued by the people that maintain these databases is 'The bigger the database the more effective it is in terms of being able to make accurate predictions on the likelihood or otherwise of you being present at the crime'.

"So on the one hand you can see a privacy issue, on the other there is an argument as to the accuracy of the science, which is then enhanced by the provision of that sample," he said.

Findlay said the issue was further complicated by whether a person had consented to a DNA sample being taken.

"If you consented to your DNA being taken, that's one thing. If the DNA was taken from you through a court order, you might say there is an even stronger argument to have it removed, but, as I said, there is a scientific argument that says the smaller the database the less effective it is in being able to make comparisons - so there is a conflict of interest there," he said.

"Maybe the answer is there should be a process whereby an application can be made to have the DNA sample removed and that application gets considered on its merits."

The Standing Committee of Attorney-Generals has considered the possibility of an application, he said, but nothing has yet been formalised.

UK shadow immigration minister Green was informed in a letter from Metropolitan Police that his case could be treated as "exceptional".

Last year, the European Court made a ruling that the opportunity for police in England, Wales and Northern Ireland to retain indefinitely genetic profiles of everyone arrested for a recordable offence were indiscriminate and must be scrapped - but governments are yet to respond.

Green told BBC News that the UK Government was behaving pretty disgracefully and dragging its feet as slowly as possible.

"There are hundreds of thousands of other people who were in the same position as me ... Where they are completely innocent and yet the police are going to hang on forever to all their details," he said.

"I just think that's intolerable in a democratic society. People have a democratic right to privacy and the law needs to be changed."

- Sarah Sharples