Attorney General William Barr and President Donald Trump have continually asserted that the Robert Mueller-led investigation into Russian interference in 2016 was fabricated and politically motivated. Now, a prosecutor chosen by Barr has reportedly contradicted this narrative, saying there’s no proof to support this theory.

Those with inside knowledge have told the Washington Post that Connecticut federal prosecutor John Durham, tasked by Barr to conduct an independent review of the Mueller investigation, is expected to have these findings included in a report set for release Monday. These sources say the report will state that there was no legal wrongdoing or attempts at entrapment aimed at the Trump campaign.

Durham’s conclusion reinforces the assertion by Justice Department Inspector General Michael Horowitz that the Mueller investigation was carried out appropriately and legally. Another key finding expected to appear in Horowitz’ report is that the FBI was justified in placing former Trump campaign policy adviser Carter Page under surveillance. The FBI’s focus on Page has been hotly criticized by Trump and his camp.

Horowitz’ upcoming report will serve to let air out of a persistent theory that has been floated by Trump and his supporters that the Mueller investigation and allegations of collusion with Russia were the actions of a “deep state” intent on undermining the current administration. This will be a major victory for Democrats, as they had previously characterized Durham’s investigation as an act of political revenge by the Trump administration.

In anticipation of this report, however, Barr has reportedly said that these findings will not be the definitive answer to whether or not the FBI’s investigation was legal. It is not clear what actions the attorney general intends to take next, however.

Durham has earned a reputation as a diligent federal prosecutor, having been called on by the Justice Department several times in the past to investigate potential government corruption. Under then-Attorney General Janet Reno, Durham was called on to review the use of informants by the FBI in Boston and, in 2008, was tasked with examining the CIA’s destruction of evidence linked to the agency’s use of torture.

US President Donald Trump (L) and Attorney General William Barr
US President Donald Trump (L) and Attorney General William Barr AFP / NICHOLAS KAMM