The Justice Department's investigation of John Brennan and its 'grand conspiracy' probe

In April 2026, shortly after the department appointed Joe diGenova, a conservative ally of Trump, to take over the investigation, it subpoenaed several witnesses to testify before a federal grand jury in Washington. A Florida-based career prosecutor who had helped lead the inquiry left the case after expressing doubts about the legal viability of a prosecution.^[7] In July, Brennan sued the administration, asking a court to order officials to preserve the records of the investigations targeting him, which he said he would need to defend himself against any eventual indictment.^[1]

In September, diGenova left the department after five months leading the wider investigation into Trump's foes without charging a single case, and the department pressed on with subpoenas.^[3] Shortly before leaving, he signed a subpoena summoning Brennan to testify in October before the Florida grand jury; Brennan also remained the target of a separate inquiry into whether he made false statements.^[2] Kurt Olsen, a lawyer who had backed Trump's false 2020 election claims, then resigned from the probe as well.^[4] Brennan has denied wrongdoing and accused the department of pursuing him for political reasons.^[2]

In October, released memos showed that notes from a secret 2023 meeting between then-special counsel Jack Smith's team and Brennan had been left blank.^[8] On October 15, a federal judge in Washington dismissed Brennan's lawsuit, ruling that he did not yet have standing to sue over the investigation, which targets him for his role in reviewing the 2016 election.^[5]