Patel did not immediately return a request for comment.

Boyd’s letter to Nunes referred to the document as “a staff-drafted memorandum that purports to be based on classified source materials that neither you nor most of them have seen.”

A separate congressional source confirmed that Patel helped write the Nunes memo.

The committee’s staff director, Damon Nelson, also contributed to the memo, the source told me, adding that Nelson is extremely close to Nunes. Nelson served as Nunes’s deputy chief of staff for 11 years, between 2003 until 2014. A congressional official told The Guardian last August that Nelson was involved in the decision to send Patel and Presley to London. Another former Nunes staffer who now works for the committee, Andrew House, also worked closely with Nelson on the memo, the source added.

The Nunes memo is not Patel’s first foray into the FISA and unmasking controversy that was drummed up by his boss back in March 2017. Patel circulated an internal memo last November urging Nunes to hold top officials at the Justice Department and the FBI in contempt of Congress for failing to turn over documents related to the Obama administration’s alleged use of the dossier to surveil Trump associates during the transition period, one of the sources told me. That memo was first reported by Fox News in November.

Patel also formally invited Erik Prince to testify before the House Intelligence Committee last summer following a meeting between Prince and Nunes “over the summer or early fall,” according to a transcript of Prince’s interview, which was conducted on November 30. The meeting raised eyebrows given Nunes’s recusal from the Russia investigation at the time and Prince’s status as a witness in that probe.

Prince was questioned by the committee about his meeting with Emirati government officials and a Russian hedge-fund manager in Seychelles just before the Inauguration. His prior conversation with Nunes, he told the panel, revolved around Nunes’s “investigation into the unmasking of intelligence on Americans.”

Patel set off for London last summer without first informing Ranking Member Schiff and Republican Representative Mike Conaway, who took over the panel’s Russia probe after Nunes stepped aside last April. The trip was characterized by a committee official at the time as an “intelligence committee trip” whose main purpose was not to meet with Steele, one of the sources told me. Steele’s lawyer denied the staffers’ access to his client.

A Nunes spokesman did not immediately return a request for comment.

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