Kash Patel, Rep. Devin Nunes’ (R-CA) former top aide, is reportedly serving as an aide to acting Director of National Intelligence Richard Grenell.

Politico reported that Patel began his new role on Thursday. He previously worked for the White House’s National Security Council after he had left Nunes’ office.

As Nunes’ aide, Patel helped craft the infamous “Nunes memo” back when the California Republican was the chair of the House Intelligence Committee in early 2018.

The memo, which aimed to discredit Special Counsel Robert Mueller’s Russia investigation by “proving” anti-Trump bias in the intelligence community, was widely mocked upon the document’s release for its sloppy mischaracterizations and omissions of key facts in House Republicans’ accusations.

Additionally, key impeachment witness Lt. Col. Alexander Vindman, who served as the NSC’s Director for European Affairs before he was suddenly ousted by President Donald Trump, testified that Patel had misrepresented himself to Trump as an expert on Ukraine, despite the fact that he had no experience with the Eastern European country and that Vindman was the true expert on the matter.

Patel’s involvement with Ukraine policy transpired around when Trump and Rudy Giuliani were plotting to withhold aid to Ukraine as a means to pressure the Ukrainian president into announcing an investigation into Joe Biden.

A spokesperson for the Office of the Director of National Intelligence declined to comment on the record.