President Donald Trump is not happy with the Supreme Court. Again.

After his administration's mail-in voting restrictions got blocked, Trump took to Truth Social on Tuesday to vent, calling the decision a "big loss" for Republicans with the 2026 midterm elections looming.

Trump Slams Supreme Court Mail-In Voting Ruling

In his post, Trump said Republicans had received "another bad decision" from the Supreme Court, and he accused the justices of dragging their feet on issuing the ruling.

He didn't hold back on mail-in voting itself, calling it a "totally CORRUPT and out of control" "disaster" and arguing the decision would make "cheating by the Radical Left 'Dumocrats,' on Mail-In Ballots" easier.

"It is a big loss for Republicans, and America itself," Trump wrote.

He added, "The Supreme Court has really let our Country down!"

There was praise for some justices, though. Trump called Justices Samuel Alito and Clarence Thomas "legends" and noted that they strongly disagreed with the ruling.

Then came the part that stings a little more personally. Trump criticized three judges he appointed during his first term: Brett Kavanaugh, Neil Gorsuch and Amy Coney Barrett, writing, "These are not the people I interviewed to serve on the United States Supreme Court."

He didn't stop at voting, either. Trump broadened his criticism to other rulings, saying the court's decisions on tariffs and birthright citizenship were "horrible" and "destructive."

Supreme Court Blocked USPS Ballot Rules

So what actually happened? On Monday, the Supreme Court rejected the Trump administration's request to immediately enforce new USPS requirements for federal election ballot mail ahead of the 2026 midterms.

Kavanaugh said implementing the rules would have been "arbitrary and capricious" because election officials simply lacked enough time to make it work.

Alito and Thomas dissented, with Alito arguing that USPS had broad authority to regulate mail.

Trump's Mail-In Voting Rules

This isn't the first setback for the administration on this front. Last month, a federal judge blocked key parts of Trump's mail-in voting overhaul, ruling that the executive branch lacked the authority to regulate elections.

That ruling expanded an injunction covering 23 Democratic-led states and Washington, D.C., and prevented the administration from changing ballot-mail rules ahead of the Nov. 3 midterms.

The whole fight traces back to Trump's March executive order, which sought to tighten mail-in voting by having federal agencies help verify eligible voters and requiring absentee ballots to be sent only to voters on approved state lists.

Trump has said the order was meant to ensure "voter integrity" and "honest voting."