The report by a former Appeal Court judge, Sir Iain Glidewell, was delivered to the Attorney General, John Morris, on Monday, and is understood to call for wide-ranging reforms of the Crown Prosecution Service, which Dame Barbara heads.
Dame Barbara said the reason for her decision to leave early was that she wished her successor to be in place in time for the major reorganisation of the CPS being planned by the Government. "It is important that a new management structure should be put in place by the team who will see it through," she said.
The Attorney General accepted her decision and praised the DPP for her "strong and positive leadership" of the CPS.
While in opposition, senior Labour figures mounted a forceful campaign against the CPS. The Glidewell inquiry was ordered within weeks of taking office.
Dame Barbara has also come under pressure to resign over the failure to prosecute police officers implicated in the deaths of two men in custody. Retired judge Gerald Butler has completed a report into those decisions - which were later quashed in the High Court - but the CPS has declined to publish it ahead of impending court action.
Yesterday, the Government closed ranks in support of Dame Barbara, and the Prime Minister's spokesman said Tony Blair considered that she had done "an extremely good job".
But her departure was well received in many areas of the police service. Sergeant Mike Bennett, chairman of the Metropolitan Police Federation, who once dubbed the CPS "Criminal Protection Society", welcomed the news.
"I'm pleased she's gone - she should have gone a long time ago," he said. "She would never listen to her critics."
Dame Barbara, 57, will continue as DPP until her successor has been appointed and is in post. She had been due to retire in April 1999 and had already indicated that she did not seek an extension of that contract.
She joined the CPS from the Serious Fraud Office, where she was director for 18 months from September 1990.
In a statement issued yesterday she said she had been "very proud" of her role over the last six years, and paid tribute to her staff and management team. "The process of change is not at an end," she said.
The Government has already decided that the CPS should be organised on police force lines into 42 areas, each with its own Chief Crown Prosecutor.
The 11-month Glidewell inquiry, which comes against a background of falling numbers of prosecutions, is said to have concluded that the rigid CPS , based on a powerful headquarters in London, has created extra paperwork for lawyers and reduced efficiency. It is expected to highlight a series of management shortcomings and low morale within the service.Reuse content