Scottish police may be handed powers to store DNA profiles and fingerprints of anyone they have arrested.
Under the plans police will be able to store fingerprints and DNA
The Scottish Executive is to launch a three-month consultation on the idea following pressure from police chiefs.
Under the plans, evidence taken from a person could be retained even if they are subsequently found not guilty.
Opposition parties and human rights campaigners are against the idea, claiming it is a move towards the creation of a "police state".
Westminster's Criminal Justice and Police Act 2001 has enabled forces in England and Wales to retain all prints and DNA samples, even if there is no prosecution, or the individual is acquitted.
At the time, the executive rejected the introduction of similar powers across Scotland.
However, the Criminal Justice (Scotland) Act, passed in February 2003, allows police to retain DNA and fingerprints given voluntarily.
A spokeswoman for First Minister Jack McConnell said the executive remained "neutral" on the issue but believed a debate on the issue was required.
The government acknowledged concerns about civil liberties but said the consultation would allow the powers to be introduced as part of the upcoming Police Bill if ministers deemed them necessary.
A spokeswoman said: "We are responding to calls from the police to have a look at this as they feel it might help them clear up more crimes.
"It's a three-month consultation and if there was to be a decision to take this forward it would need legislation and we could use the Police Bill, which is expected to be introduced to parliament in the next session.
"This has been happening in England and Wales for the last four years.
"We took the view at the time not to do that but now we are saying 'let's have a proper debate' and look at all the arguments for and against."
Annabel Goldie is concerned about civil liberties
Scottish Human Rights Centre chairman John Scott said the executive must reject the idea.
The criminal lawyer said police had no more right to retain the prints or DNA evidence of a suspect who was never charged or cleared by a court than those of the population at large.
Mr Scott said: "This would be a worrying continuation of a trend where the rights of the individual are ignored in favour of the state.
"Unfortunately, this is all part of the same march towards the sort of potential for a police state that we have had warnings about in the past and which people don't take seriously.
"The infrastructure is steadily coming to pass and I hope the executive will show the same caution on this as it has in relation to ID cards."
Labour's coalition partners, the Scottish Liberal Democrats, are understood to be particularly uneasy about the proposals and insisted that the consultation be worded in neutral terms.
A senior party source said today: "We are sceptical about this and while we will await the outcome of the consultation, to overcome that scepticism there would require to be some unquestionably significant and unarguable evidence."
Opposition parties also expressed concern about the plan.
Kenny MacAskill, the Scottish National Party's justice spokesman, said it could lead to a "Big Brother" state.
"This encroaches too far into our individual human rights," he said.
"If such a scheme is to be implemented in Scotland, we would have to be fully satisfied and assured that this is not part of some Big Brother exercise that would see further state monitoring and control of individuals' actions.
"Everyone wants to fight crime, but we have to ensure that in doing so we do not criminalise the innocent."
Scottish Tory justice spokeswoman Annabel Goldie added: "I am anxious to see the full details of the Executive's proposals, but I do have concerns about individual civil liberties.
"There is a danger, for example, that those who freely offer DNA samples in an investigation might be more reluctant to come forward in future.
In a brief statement the Association of Chief Police Officers in Scotland (Acpos) said: "Acpos welcomes the opportunity to debate the proposals to retain fingerprint and DNA samples and will carefully consider its position on that matter."