Judge Philip Shorrock said most rape trials led to the rapist being 'unsurprisingly' acquitted because of drinking or drugs

A judge has launched an unprecedented attack on the head of the Crown Prosecution Service over her handling of rape trials.

Judge Philip Shorrock claimed that Alison Saunders, the Director of Public Prosecutions, had less understanding of the cases than a newspaper columnist.

He said in his 40 years as a barrister and on the bench, most trials led to the alleged rapist being 'unsurprisingly' acquitted because both parties had been drinking or taking drugs, and there was no independent proof of what had happened.

But last night, in an extraordinary outburst, Mrs Saunders hit back and accused the judge of peddling old-fashioned views.

The DPP said: 'It is always disappointing to hear views expressed that lean in favour of the 'victim blaming' culture that allowed sexual predators to offend with assumed impunity in days gone by.

'It is our job, as prosecutors, to make objective charging decisions based on the evidence, rather than the discredited rape myths that skewed the system against victims.'

It is the latest in a series of embarrassing public clashes between the judiciary, politicians and officials over the highly contentious issue.

First, retiring judge Lindsey Kushner warned women that predators 'gravitate towards girls who have been drinking' – leading to accusations by former Labour Minister Dame Vera Baird that the judge was blaming victims.

Mrs Saunders has said the judges views lean in favour of the 'victim blaming' culture

And last week, the Lord Chief Justice, Lord Thomas, declared that the Justice Secretary Liz Truss was 'wrong' when she announced that all rape complainants would soon record their evidence on film to spare them cross-examination in open court.

Then Daily Telegraph columnist Allison Pearson claimed the 'militant sisterhood' of Miss Truss and Mrs Saunders were abandoning the principle that men accused of rape are innocent until proven guilty. The DPP responded to her by insisting the CPS had not changed the law on consent. Mrs Saunders insisted the CPS had to charge people where there was a realistic prospect of conviction'.

But in a highly unusual break with protocol, Judge Shorrock wrote to the Telegraph explicitly criticising the DPP, suggesting she did not know why many rape trials concluded with an acquittal.

The row comes just a few weeks after retired judge Lindsey Kushner warned that women who had been drinking are more at risk of rape

He said in most cases 'the complainant and the defendant know one another'.

'One or both has or have been drinking and or taking drugs before the events giving rise to the complaint taking place,' he wrote. 'If my experience is any guide, I fear that Allison Pearson's analysis is closer to the mark than that of Alison Saunders.'

The Judicial Office said no complaints had been received. However, the Guide to Judicial Conduct states that judges should use their freedom to comment in the media with 'the greatest circumspection'.

In addition, they 'should not air disagreements over judicial decisions in the press', and must consider the 'risk of expressing views that will give rise to issues of bias or pre-judgment'.