Donald Trump's allies have branded his own Supreme Court pick Amy Coney Barrett a 'turncoat' after she authored the majority opinion handing the President a stinging defeat on mail-in ballots. The ruling upheld a Mississippi law letting mail ballots arrive up to five days after Election Day, slamming shut a legal route for Trump in his war on postal votes, which he claims without evidence enable the fraud he blames for his 2020 defeat. The court voted 5-4 with Trump-appointed Barrett penning the opinion which was joined by Chief Justice John Roberts, as well as liberal justices Sonia Sotomayor, Elena Kagan and Ketanji Brown Jackson. Prominent conservatives including Steve Bannon and Megyn Kelly railed against Barrett's opinion on Monday. 'Amy Coney Barrett. Man, she was a lovely pick. Did anybody do any due diligence here? Right to life crowd, did you do your due diligence? Are you happy with what you got?' Bannon said on his War Room podcast, a jab at the Catholic credentials used to sell her conservatism when Trump nominated her in his first term. Megyn Kelly said on her show: 'Amy Coney Barrett is a turncoat, she's constantly sitting with the left.'

Republican Senator Eric Schmitt called it 'a shockingly wrong opinion' slamming Barrett for joining 'liberal justices' in a decision that 'is terrible for election integrity.' Trump called the decision a 'tremendous loss' in a Truth Social post, later telling reporters in the Oval Office it was 'a little bit surprising' and claiming it 'gives people more time to vote illegally.' Barrett bluntly rejected arguments that federal election laws supersede Mississippi's statute allowing late-arriving absentee ballots. 'The election-day statutes do not set a deadline for ballot receipt, so they do not prevent Mississippi from counting ballots postmarked before election day yet received afterward,' she wrote.

Justice Samuel Alito penned a ferocious dissent, writing: 'From this Nation's founding until the last few decades of the 20th century, a period that spans the enactment of all three election-day statutes, having an "election" on a particular day meant completing ballot collection on that day.' Justices Clarence Thomas and Neil Gorsuch signed Alito's dissent in full. Brett Kavanaugh backed his bottom line and his warning that late ballots invite fraud, but stopped short of endorsing two stretches of Alito's reasoning.

The defeat sharpens Trump's push for the SAVE America Act, his stalled voting bill demanding proof of citizenship to register and photo ID at the polls. It would gut mail voting entirely, sparing only the sick, disabled, travelling and deployed troops. Trump has already torched a landmark bipartisan housing bill over the deadlock, refusing to sign the first major fix to the housing crisis in three decades until Congress moves on his election overhaul. Documented mail-ballot fraud is vanishingly rare. A Brookings Institution study last November logged an average of four fraud cases per 10 million votes across the last five US elections.

Trump himself cast a mail ballot in a Florida special election earlier this year. RNC chairman Joe Gruters vowed the fight goes on, accusing Democrats of 'inviting chaos at the ballot box by allowing elections to drag on for days and weeks after voters cast their ballots.' More than a dozen states allow mail-in ballots to be counted after Election Day, including Alaska, Texas, Nevada, Virginia and California. California Governor Gavin Newsom celebrated the ruling. 'This is a win for voters, plain and simple,' Newsom said on X. 'Today's ruling helps ensure mailed-in-ballots get counted and people's voices are heard through the democratic process.'