Former President Donald Trump has relentlessly tried to block allowing members of his inner circle to testify about his actions leading up to and during the January 6th riots at the United States Capitol building.

However, Bloomberg legal reporter Zoe Tillman writes that the former president's "string of losses" in court has now left him without any options -- and now grand juries are starting to hear from his closest confidants.

In particular, notes Tillman, longtime Trump loyalist Stephen Miller and former Director of National Intelligence John Ratcliffe were spotted going into a grand jury room at the Washington D.C. federal courthouse this week, which suggests that special counsel Jack Smith has successfully breached all of Trump's defenses in attempting to block testimony.

On top of this, Trump's efforts to block former Vice President Mike Pence from testifying are now hanging by their fingernails.

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"The witnesses at the heart of Trump’s executive privilege fights, who once occupied top administration posts, are poised to take grand jurors inside the White House during tense exchanges after the election and in the weeks leading up to the Jan. 6 US Capitol attack," writes Tillman, who expects grand jurors will now hear about "Oval Office clashes over a proposal to seize voting machines, Trump’s plan to install a sympathetic acting US attorney general, and a pressure campaign urging Pence to disrupt the election certification by Congress based on slates of fake electors."