The Crown Prosecution Service was aware in 2015 that its conviction rate 'levels of ambition' could have unintended consequences, the Gazette can reveal.

The service is facing a judicial review brought by a coalition of women’s rights organisations who argue the service has become more risk averse in its policy on rape cases. Numbers of rape prosecutions and convictions have fallen drastically in recent years despite record levels of allegations.

The Gazette revealed last year that the levels of ambition - for rape, domestic violence and hate crime - were in operation at the CPS between 2016 and 2018 and were enforced by the service’s inspectorate, HMCPSI.

For rape, the ambition was for at least 60% of charges to end in conviction. During the period the measure was in force, the percentage of charged cases ending in conviction rose but actual numbers of convictions fell, raising fears prosecutors were weeding out weaker cases.

A CPS spokesperson told the Gazette last year that the levels of ambition had been dropped over fears they might act as a 'perverse incentive'. The CPS has since denied the levels of ambition were used as targets at all, insisting they were simply performance indicators. Siobhan Blake, CPS national lead for rape and serious sexual offences, told the Gazette: 'It is not the case we believed they were creating perverse incentives.'

However a 2015 report of a consultation with chief crown prosecutors and area business managers, released by the CPS following the Gazette’s Freedom of Information Act request, made it clear that the levels of ambition were expected to drive up conviction rates.

The report stated: 'The rape conviction rate has been falling for the past two years and now stands at 57.2% for the calendar year 2014. It is therefore appropriate to propose a level of ambition of 64% for 2015/16.'

The same document warned against increasing the level of ambition for domestic violence cases, stating: 'It is important not to set the rate too high which may in turn encourage unintended consequences.'

The rape level of ambition was later lowered from 64% to 60% by the head of operations and chief operating officer, following further consultation, the CPS said. The CPS did not provide any other details of this further consultation. The Gazette is currently appealing the response.

Efforts by the Gazette to obtain evidence of the decision-making behind the abandonment of the levels of ambition have produced few results. To date the CPS has failed to produce a single documentary record of the decision in its response to two FOI requests filed by the Gazette.

In place of documents, the CPS offered a summary of events, stating: 'The decision to cease the use of levels of ambition for all conviction rate measures was made by the director of public prosecutions… this decision was passed down through normal line management arrangements and enacted accordingly.' 

A CPS spokesperson said: 'The CPS regularly reviews what internal management information is tracked, to inform performance discussions. Senior leaders across the organisation have an opportunity to contribute views when changes are considered, but decisions will be made by members of the executive group.

 'We continue to monitor case outcomes but removed levels of ambition for conviction rates in 2018.'

Latest data shows rape prosecutions fell 26% in the year to September 2019 and numbers of convictions fell by 21%.