Keir Starmer has said Jeremy Corbyn was demonised by the press during the election campaign.
The frontrunner to be Labour’s next leader, who has refused to give interviews to The Sun, also claimed there had been “vilification of Labour leaders” in the past.
The shadow Brexit secretary told Sky News Sophy Ridge on Sunday that voters who said they didn’t like Corbyn had come to a judgement because of “what had been fed into them by the press” and that UK media risked losing “any kind of balance”.
He said: “I defend journalists and it is very important that we do but in elements of the press there’s been vilification of Labour leaders that’s gone on for many, many years and Jeremy Corbyn probably got it worse than any leader this time.
“When we went and knocked on doors and people said they didn’t like Jeremy Corbyn, quite a bit of that was what had been fed into them by the press.
“We do need to address this because in the end, if we lose any kind of balance in the coverage of politics, we’re on a slippery slope.
“You can have an honest discussion all you like about politicians and politics, but once you’re on that slippery slope, then we’re losing touch with what actually matters.”
Many Labour members blame the media for Boris Johnson winning an 80-seat majority at the election, with one YouGov poll of the party’s grassroots saying Corbyn had been the best Labour leader of the last century.
Starmer is the clear frontunner to take the top job, with strong union backing and a majority of local Labour parties throwing their weight behind his campaign.
He faces competition, however, from shadow business secretary Rebecca Long-Bailey and campaigning Wigan MP Lisa Nandy, who has stressed the need for the party to regain voters in towns.
Pressed by Ridge on whether he felt closer to Corbyn’s politics or those of New Labour’s Tony Blair, Starmer refused to be tied down.
He said: “If we can’t unite our party and stop taking lumps out of each other, then we’re not going to win the next general election and so I want to bring our party together.”
Starmer turned his fire on the prime minister in the wake of this week’s reshuffle, when chancellor Sajid Javid resigned rather than have Number 10 dictate who his team of advisors could be.
He said the PM’s chief adviser Dominic Cummings was behind Javid’s dramatic exit and said parliament will “have to have DCQs for Dominic Cummings before too long” in place of PMQs (prime minister’s questions).
He said: “Dominic Cummings is just getting more and more power. I know Boris Johnson doesn’t much like coming to Parliament, he does at least come for PMQs.
“I think we’re going to have to have DCQs for Dominic Cummings before too long because he is actually holding all the power and how do we hold him accountable?”