Republicans on the House Judiciary Committee and the House Intelligence Committee repeatedly asked Special Counsel Robert Mueller why he never indicted Joseph Mifsud, who was key to the Russia collusion narrative.

They appear to believe that Mifsud was possibly used by opponents of then-candidate Donald Trump to implicate his campaign in wrongdoing, and provide the basis for later surveillance and investigation (as well as, though they did not succeed, prosecution and impeachment).

Mifsud was key to the prosecution of junior Trump campaign foreign policy aide George Papadopoulos, who admitted that he lied to the FBI about meeting Mifsud before joining the campaign. (They had met afterwards.)

As Breitbart News has noted:

Their [the media] story reportedly was that a Maltese professor named Joseph Mifsud told Papadopoulos the Russians had dirt on Hillary Clinton in the form of thousands of emails, and Papadopoulos passed that on during a meeting at a bar with Australian diplomat Alexander Downer in London, prompting Downer to tell U.S. officials, and prompting the FBI investigation. However, Mifsud’s lawyer would later tell CNN and other outlets that the professor was never a Russian agent, but instead working on behalf of Western intelligence.

The International Business Times adds (original links):

A report in October from the Associated Press described Mifsud as having a “bizarre academic career punctuated by scandals and disappearing acts.” Some have rumored that Mifsud has died, but his Swiss-German lawyer, Stephan Roh, told the AP that Mifsud is still alive. Mifsud faced scandals in the early 2000s while working at the University of Malta, where he was accused of “financial mismanagement.” He then disappeared in 2007 and began to work at the Euro-Mediterranean University in Slovenia. He reportedly left the university with close to the equivalent of tens of thousands of dollars in debt, before vanishing once again. Mifsud then began working at the London Academy of Diplomacy in 2013. It was is in London that Mifsud met Trump’s advisor Papadopolous to discuss the Russia emails.

The Mueller report itself says:

Campaign foreign policy advisor George Papadopoulos made early contact with Joseph Mifsud, a London-based professor who had connections to Russia and traveled to Moscow in April 2016. Immediately upon his return to London from that trip, Mifsud told Papadopoulos that the Russian government had “dirt” on Hillary Clinton in the form of thousands of emails. One week later, in the first week of May 2016, Papadopoulos suggested to a representative of a foreign government that the Trump Campaign had received indications from the Russian government that it could assist the Campaign through the anonymous release of information damaging to candidate Clinton. Throughout that period of time and for several months thereafter, Papadopoulos worked with Mifsud and two Russian nationals to arrange a meeting between the Campaign and the Russian government. No meeting took place.

The report adds that Papadopoulos’s false statements about his meeting with Mifsud “hindered investigators’ ability to effectively question Mifsud when he was interviewed in the lobby of a Washington, D.C. hotel on February 10, 2017.”

It goes on to say that Mifsud himself made false statements to FBI investigators, denying the extent of his contacts with Papadopoulos, and denying “that he had advance knowledge that Russia was in possession of emails damaging to candidate Clinton, stating that he and Papadopoulos had discussed cybersecurity and hacking as a larger issue and that Papadopoulos must have misunderstood their conversation.”

Republicans asked Mueller several times why Mifsud had not been prosecuted for making false statements to the FBI, when others — including Papadopoulos, former National Security Advisor Michael Flynn, and former Trump campaign manager Paul Manafort — had been.

Mueller declined to comment on that. However, given previous reports that the FBI used at least one source to infiltrate the Trump campaign, Republicans seemed to be implying that Mifsud had been spared prosecution for a reason.

Ranking member of the House Intelligence Committee Devin Nunes (R-CA) said in May that he believed Mifsud had ties to the U.S. State Department. As the Washington Examiner noted at the time, Nunes sent a letter to the Special Counsel detailing Mifsud’s ties to Western agencies, and included a photograph with Mifsud and British politician Boris Johnson — who became prime minister Wednesday, and who was mentioned at the hearing.

In the letter, Nunez raised the possibility that Mifsud was an intelligence risk to the U.S. and its allies, if he was indeed a Russian operative, as the Special Counsel’s report suggested. Alternatively, Nunes said, the FBI had been using Mifsud as an informant, which would explain why it knew to ask Papadopoulos about Clinton’s emails.

Attorney General William Barr is currently conducting an investigation into the origins of the investigation of the Trump campaign. Republicans are flagging Mifsud as someone Barr needs to understand in the course of that inquiry.