(CNN) — Evan Corcoran, Donald Trump’s primary defense attorney, appeared Friday before a federal grand jury in Washington, where he was expected to answer questions in the classified documents probe that the former president unsuccessfully fought to hold back.

His appearance before the grand jury has the potential to make or break the special counsel’s investigation into the handling of classified records at Mar-a-Lago and possible obstruction of justice when the federal government tried to get the documents back.

Corcoran has been told by the federal court he cannot withhold information any longer about communications he had with Trump, his client, leading up to the FBI search of Mar-a-Lago last summer. He was also ordered earlier this week to turn over notes he had considered to be his written work as an attorney in the probe. Corcoran would have had a window into many of the moments where Trump and his team were responding to the federal government’s efforts to get classified documents back.

Prosecutors have made clear in court proceedings that are still under seal that they believe Trump tried to use Corcoran to advance a crime.

A Trump spokesperson criticized the recent developments, saying, “Prosecutors only attack lawyers when they have no case whatsoever.”

When Corcoran first testified to the grand jury in January, he was asked about what happened in the lead up to the August search of Trump’s Mar-a-Lago residence. But he declined to answer, prompting the prosecutors to take the unusual step to fight in court to force him to respond.

Prosecutors now want to ask Corcoran about his interactions with Trump regarding a May subpoena and subsequent search for classified documents at Mar-a-Lago. They also want to know about the statement Corcoran crafted in June 2022 — which claimed a “diligent search” had been conducted of boxes moved from the White House to Florida — and a June call between Trump and Corcoran that took place the same day the Trump Organization was subpoenaed for surveillance footage of Mar-a-Lago, according to a person familiar with the matter. The surveillance footage ultimately showed boxes being moved out of a storage room within the resort, which a witness later said happened at Trump’s direction.

That June statement, which also said all classified documents had been returned, included the signature of attorney Christina Bobb, who added the caveat, “to the best of my knowledge.”

Later that summer, the FBI searched Mar-a-Lago and found hundreds of government records, including classified material, raising questions about the lawyer’s attestation.

Corcoran’s second visit to the grand jury Friday comes well into the year-long criminal investigation around the classified records Trump kept.

Months ago other close advisers to Trump were brought in to testify, and more than two dozen aides and staff around Mar-a-Lago have been subpoenaed to the grand jury, CNN has reported.

Even on Thursday, the grand jury investigating the Mar-a-Lago documents was pressing forward hearing from an unknown witness. Special counsel’s office prosecutors have been demanding others testify as well, now often unwilling to give deadline extensions, according to multiple sources familiar with the probe.

Trump’s various legal entanglements in Florida, Georgia and New York have come increasingly into public view in recent days, especially regarding the case in Manhattan, where a grand jury is investigating Trump’s alleged role in a scheme to pay hush money to adult film star Stormy Daniels before the 2016 election. Trump has denied involvement while stirring anxieties of potential political violence by claiming his arrest is imminent and calling on his supporters to protest.

Such language has drawn concerns from some Republicans, including House Majority Leader Steve Scalise, a Louisiana Republican who himself was the victim of political violence in 2017.

There is “no place in America for political violence of any kind,” Scalise said Friday, after Trump warned of possible “death and destruction” if he is indicted.

Scalise added: “I’ve been saying that for years and I think everybody ought to take that position.”

This story has been updated with additional reporting.

Trump attorney appears before grand jury in Mar-a-Lago classified documents probe