New York, New York - Members of Donald Trump's entourage, including a potential vice presidential pick, live-tweeted from the ex-president's historic criminal trial Monday in an unorthodox effort to discredit star witness and former Trump fixer Michael Cohen.

Trump himself has been placed under a gag order by the judge overseeing the case, Juan Merchan, who has threatened the 77-year-old with jail if he directly criticizes trial witnesses.

That includes Cohen and Stormy Daniels, the adult film star who says she received a $130,000 hush money payment from Trump lawyer Cohen to stay quiet during the 2016 presidential campaign about her alleged sexual tryst with Trump.

But that did not stop his son Eric Trump and US senators including JD Vance from showing up at the Manhattan court and posting their own withering attacks against Cohen on social media, and insisting the charges against the Republican candidate are politically motivated.

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"I have never seen anything more rehearsed!" Eric Trump, executive vice president of the Trump Organization and one of his father's only relatives to appear in the courtroom during the weeks-long trial, wrote on X as Cohen answered prosecutors' questions.

The younger Trump, seated just behind his father, was joined by Vance, who is in contention to be Trump's running mate for the November election.

"Michael Cohen admitting he secretly recorded his employer. Just totally normal conduct, right?" Vance posted.

He also slammed the media for suggesting Trump's mental fitness is flagging because of reports he has been falling asleep at times during the trial.

"It's an absurd narrative. I'm 39 years old and I've been here for 26 minutes and I'm about to fall asleep," Vance wrote.

At the back of the courtroom sat another ally, Andrew Giuliani – son of Trump's disgraced former lawyer Rudy Giuliani – who unleashed a barrage of more than 50 tweets, most attacking "convicted felon" and "serial liar" Cohen and smearing the Manhattan district attorney who brought the case.

During a break in Monday's proceedings, Senator Tommy Tuberville decried the lack of respect given to his "friend" Trump and slammed the conditions inside the Manhattan courthouse.

"This is New York City, the icon of our country, and we've got a courtroom that's the most depressing thing I've ever been in," Tuberville told reporters.

"Mental anguish is trying to be pushed on the Republican candidate for the president of the United States this year. That's all this is," he added.