The detailed review, which will begin in May, will look at the first six months of means testing. It will evaluate the way the scheme has operated and its impact on the wider criminal justice system, but will not assess the policy itself or look at alternatives. The outcome of the review will be published.

Meanwhile, information released by the Department for Constitutional Affairs (DCA) under the Freedom of Information Act 2000 has shown that some areas have had to grant large numbers of adjournments where solicitors have refused to act.

Avon and Somerset reported particular problems, with 132 adjournments for legal aid in one week in Bristol, 29 in north Somerset and 25 in Taunton. The courts also noted that more defendants were going unrepresented, which was slowing down the court process. Plymouth, Teesside, Manchester, Liverpool and Reading also reported problems as a result of adjournments, while courts in Coventry and Birmingham were less likely to grant them.

Andrew Keogh, partner at Tuckers in Manchester and founder of information service Crimeline, which obtained the report, said: ?This shows the true impact of means testing, and also shows that when solicitors stand up for themselves and for their clients, it exposes the weakness of government policy.?

A DCA spokesman insisted that means testing is working well in some areas, and noted that the report covers a period when the regime was bedding in. He said that changes have already been made to the early cover scheme and a new form will be issued in the next few weeks.