Mr Howard has told colleagues that defence lawyers use the present rules as a "game" to find weaknesses to exploit. Under the rules, Crown lawyers are obliged before a trial to disclose to the defence all the information from a police investigation, including scientific reports, internal memos and witness statements; police say that sometimes this information has been used to identify informants or sensitive witnesses.
Mr Howard was forced to omit a Bill from the Queen's Speech last year, when he encountered legal difficulties, but he is now convinced these can be overcome.
"It will be very difficult, but he has found a way to do it, and is determined to go ahead," a senior Home Office source said.
The Bill, which Mr Howard plans to introduce in the next Queen's Speech in November, is certain to meet criticism from lawyers in the House of Lords. But leading Tory backbenchers said it would be strongly supported by the Conservative backbench. "It is long overdue," said John Greenway, the MP for Ryedale and a former Metropolitan police officer.
He said police had failed to prosecute in a rape case because the prosecution would have had to disclose the victim had made an earlier complaint about rape, which would have been exploited by defence lawyers.
Full disclosure of evidence by the prosecution has been an accepted principle for many years. A ruling in the Guinness case was considered a landmark and the 1993 Royal Commission on Criminal Justice said that guidelines laid down by the Attorney Generalin 1981 had been excessively widened by the appeal judges in the case of Judith Ward, who was cleared of the M62 coach bombing.
The police warned the commission it could not comply with the judgment because it could lead to the disclosure of information in linked cases. Police have also complained itcould lead to intimidation of witnesses.
"The defence can require the police and prosecution to comb through large masses of material in the hope either of causing delay or of chancing upon something that will induce the prosecution to drop the case rather than have to disclose the material," the commission said.Reuse content