Prosecutors were warned nearly two years ago that lawyers were under increasing pressure to boost rape convictions and were consequently wrongly charging men with sexual offences.

A report published in February last year highlighted a series of alarming failings in how the Crown Prosecution Service (CPS) and police handled serious sex cases.

The 108-page review by HM Crown Prosecution Service Inspectorate warned of a “vicious circle” as police sometimes handed incomplete case files to CPS lawyers already struggling with an immense backlog of casework.

The report authors said they identified a number of cases where lawyers who should have sent inadequate files back to detectives demanding they obtain more evidence to build a case but instead chose to charge a suspect because they were under “undue pressure”.

The report, called Thematic Review of the CPS Rape and Serious Sexual Offences Units, gave a worrying snapshot of an underfunded and overstretched legal system.

Its emergence comes as there were calls for a national review of rape cases after the Metropolitan Police launched an urgent review of every live rape case it is investigating following the collapse of two trials in London after it emerged officers had failed to disclose vital evidence that pointed to the defendants’ innocence.

View photos Liam Allan, who spent almost two years on bail, has alleged that rape convictions are chased 'like sales targets' Credit: Ken McKay/ITV/REX/Shutterstock More

In 2013, the CPS introduced Rape and Serious Sexual Offences regional units throughout England and Wales to process the increasing numbers of sex cases, including historic abuse allegations, being investigated by police. The CPS lawyers are handed police files to decide whether or not to charge a suspect with an offence.

The following year inspectors carried out a review of six regional units to analyse how they handled 90 sexual offence cases, including 62 rape allegations.

It found lawyers were struggling to keep up with deadlines, charging men where there was little chance of a conviction and some cases were never reviewed by a CPSLiam Allan, who spent almost two years on bail, has alleged that rape convictions are chased 'like sales targets' lawyer throughout the entire legal process.

It said that CPS was “under resourced”, with lawyers struggling to meet deadlines and some occasionally “too vigorously” applying a test about whether to charge suspects leading to court cases “that do not have a realistic prospect of conviction”.

In one of its most damning findings the report said: “Internal and external feedback from the police, counsel [barristers] and the judiciary suggests that because the workload exceeds the units’ capacity, it is difficult to achieve quality casework, from decision-making through to all the elements of preparation of a case.

“In addition, it was felt that there is considerable pressure on the CPS to improve on success rates and to prosecute more cases, which may lead to some cases being pursued even though there is little chance of obtaining a conviction after a trial.

“Further, that decisions on cases are rushed to achieve timeliness targets and then subsequently dropped when more thought is given to the detail of the case. In such circumstances the timeliness target can be a perverse driver.“

Referring to a “vicious circle” caused by police handing overworked lawyers poor files containing insufficient evidence, it said: “the delay by the CPS in providing advice appeared to put undue pressure on the lawyer to advise a charge where the evidence was lacking and the investigation required further work”.

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