The proposal by the Tory leader, William Hague, to scrap the double jeopardy rule suffered a setback yesterday when one of his most senior backbenchers said he would not support the policy change.
David Davis, the chairman of the influential Public Accounts Committee, said the plans to abolish the ancient right, which prevents people being tried for the same crime twice, would be a "serious body blow for justice in this country". His frank statement will come as an embarrassment to Mr Hague, who has been eager to use this week to highlight his party's policies on law and order.
Mr Davis, a former minister, said: "While I fully understand and support the aims underpinning this proposed change in the law, it is a reform that I cannot and will not support." Britain's "unbreakable" traditions, that all citizens are equal before the law and are innocent until proven guilty, would be "seriously damaged" if the rule was scrapped, he said.
An examination of the "double jeopardy" principle was part of the recommendations of Sir William Macpherson of Cluny's inquiry into death of the Stephen Lawrence, who was murdered in south-east London in 1993. The Tories opposed abolition of the rule when the report was published last year, but Ann Widdecombe, the shadow Home Secretary, announced the policy change last week. Miss Widdecombe said her party was promoting the move because the Government had failed to redress the balance in favour of victims of crime. But Mr Davis said: "Nobody can feel comfortable that the killers of Stephen Lawrence are still free ... But we should not let this hard case be used to make bad law."
Jack Straw, the Home Secretary, did not support scrapping double jeopardy when the report was first published but the Law Commission of England and Wales is examining the issue. An initial inquiry by the commission published in October backed Sir William's arguments; its report is expected to give a more detailed proposal and a draft Bill could be published by next year.
Mr Straw was understood to have been concerned that any change would infringe theEuropean Convention on Human Rights.