One in five Conservative voters say Keir Starmer’s record as director of public prosecutions makes them less likely to vote Labour at the next general election, exclusive polling for the New Statesman has found.

The new leader of the opposition, who headed the Crown Prosecution Service for five years from 2008 to 2013, leant heavily on his legal career during his campaign to succeed Jeremy Corbyn. His critics on the left and right, however, have sought to weaponise his record as England and Wales’s chief prosecutor to undermine his progressive credentials.

Though supporters insist it is not fair to paint Starmer as culpable for individual decisions, he has nonetheless been blamed - often inaccurately - for decisions not to prosecute police involved in the deaths of Jean Charles de Menezes and Ian Tomlinson, as well for the introduction of harsher penalties for fraudulent welfare claimants.

Polling for the NS by Redfield and Wilton Strategies, a member of the British Polling Council, suggests that media coverage of Starmer’s past career could have an impact at the ballot box.

While only 12 per cent of voters overall say they are less likely to vote for the Labour Party as a result of Starmer’s career at the CPS, 22 per cent of those who backed Boris Johnson’s Conservatives at the last general election say it makes them less likely to vote for the opposition at the next election.

The findings show a clear left-right split over Starmer’s time as DPP. More than a third – 34 per cent – of 2019 Labour voters say they are more likely to back the party again because of his previous career. More than one in four – 26 per cent – of 2019 Liberal Democrats take the same position. A minority of Conservative voters – 12 per cent – say they are more likely to vote for Labour under Starmer as a result of his record at the CPS.

Remainers and Leavers are split along similar lines. One in five – 20 per cent – of those who voted for Brexit in 2016 say they are less likely to vote for Starmer because of his record as DPP, compared to just four per cent of Remainers. By comparison, 16 per cent of Leavers and 27 per cent of Remainers say they are more likely to vote Labour.

The majority, however, appears indifferent to Starmer’s past, with 62 per cent saying they were no more or less likely to vote Labour because he was DPP. Most voters, regardless of their 2019 allegiance, EU referendum preference, age or geographical location say the Labour leader’s time at the CPS makes no difference to their voting intention.

Exactly half of all voters do not know that Starmer was DPP, with 35 per cent aware only that he held the position and 15 per cent aware of individual decisions he is reported to have taken.

The findings also suggests that viral social media content about Starmer’s record at the CPS has influenced voters, with 15 per cent saying they had seen or been sent posts blaming the Labour leader for the decision not to prosecute Jimmy Savile for child sex offences in 2009. Facebook posts making the allegation have been shared thousands of times, and have also been widely distributed on WhatsApp.

Savile, who died in 2011 and was subsequently unmasked as a prolific predatory paedophile, was interviewed by Surrey Police in 2009 over allegations of sexual assault against three teenage girls. The force decided in October that year that no action would be taken because the victims were unwilling to testify in court

A CPS review of the decision after Savile’s death, however, admitted that chances were missed to prosecute the TV personality and found that Surrey Police had not told the victims that there were other complainants. Savile's accusers told the QC Alison Levitt, who worked as Starmer’s legal adviser, that they would have probably been prepared to give evidence in court had they known about the existence of other complaints.

Starmer, who was not personally involved in the decision not to prosecute Savile, apologised after the report’s publication in 2013 and said he wanted the case to be a “watershed moment”. In a leadership interview with the BBC’s Andrew Neil this March, Starmer said of the case: “Whilst he [Savile] was alive, two women came forward to make allegations against him, in Surrey and Sussex, neither of them knew that the other existed and no prosecutions were brought... the rules were set in a completely different way.”

Redfield and Wilton Strategies polled a representative sample of 2,000 British adults online on 8 April​