Senators quizzed FBI Director James Comey on Wednesday over whether the political research firm behind the Trump dossier is part of Russia’s intelligence apparatus.

The connection between the firm, Fusion GPS, and a former Russian counterintelligence agent named Rinat Akhmetshin is one of the stranger wrinkles in the ongoing Trump-Russia saga.

The link has received little media attention since it was revealed by The Daily Caller in January, just after the dossier was published by BuzzFeed. But as Senate Judiciary Committee chairman Chuck Grassley has noted, Fusion’s affiliation with Akhmetshin raises questions about whether the research firm’s dossier work can be trusted. (RELATED: EXCLUSIVE: Oppo Firm Behind Trump Dossier Is Linked To Pro-Kremlin Lobbying Effort)

Fusion GPS was hired in June by an ally of Hillary Clinton’s to research Trump’s ties to Russia. The firm, founded by a former reporter named Glenn Simpson, hired ex-British spy Christopher Steele to dig up dirt on the Republican candidate. Steele would go on to compile 17 memos full of salacious and largely unfounded claims about Trump and several of his campaign advisers.

Despite questions about the veracity of the memos, the FBI has reportedly used them as part of its Trump investigation.

Fusion’s investigative project, which involved rooting out Kremlin secrets, appears at odds with the work for Akhmetshin, which aimed to help the Russian government and its oligarchs.

South Carolina Sen. Lindsey Graham asked Comey during a widely-watched Senate Judiciary Committee hearing on Wednesday whether Fusion GPS was “part of the Russian intelligence apparatus.”

“I can’t say,” the FBI chief said.

“Do you agree with me that if Fusion was involved in preparing a dossier against Donald Trump that would be interfering in our election by the Russians?” Graham asked.

“I don’t want to say,” Comey said, without elaborating further.

Grassley has pressed Comey and Fusion about the firm’s work, both on the dossier and with Akhmetshin. The Republican has questioned Comey about reports that FBI agents met with Steele and at one point agreed to pay him $50,000 to continue researching Trump. The bureau also cited the dossier in an application for a surveillance warrant against former Trump campaign adviser Carter Page.

“Where did the money come from, and what motivated the people writing the dossier?” Grassley asked on Wednesday.

Comey provided few answers to Grassley’s questions during the hearing. And in a response letter last month, Fusion GPS refused to cooperate with the committee, citing First Amendment protections and attorney-client privilege. (RELATED: Senator Wants Answers From Oppo Firm Behind Trump Dossier)

Fusion distributed Steele’s dossier to reporters before and after the election. In a recent court filing in London, Steele faulted Fusion and BuzzFeed for releasing the dossier. Steele is being sued by a Russian tech executive named in the final memo in the dossier. The executive is suing BuzzFeed in the U.S.

Fusion’s work with Akhmetshin involved a campaign favored by the Kremlin to roll back sanctions imposed by a 2012 law called the Magnitsky Act.

Akhmetshin lobbies members of Congress on behalf of The Human Rights Accountability Global Initiative Foundation (HRAGIF), a non-profit he founded early last year with a Russian businessman named Denis Katsyv.

Ostensibly, the group’s work had a noble goal: to help American couples adopt Russian orphans. But HRAGIF appears to have had ulterior motives: to undercut the Magnitsky Act.

The Russian government opposes the law and similar legislation because allows for the authorization of sanctions against Russians implicated in human rights abuses.

The law is named after Sergei Magnitsky, a Russian lawyer who was killed in a Russian prison in 2009 while he was investigating a fraud conspiracy involving a group of Russian oligarchs close to Russian president Vladimir Putin.

Working for a U.S.-born businessman named Bill Browder, Magnitsky uncovered a $230 million money laundering operation. Katsyv, who runs a company called Prevezon Holdings, was involved in the scheme. He is currently being investigated by the Justice Department and has been sanctioned under the Magnitsky Act.

Browder, who once supported Putin, lobbied Congress heavily to help pass the sanctions bill. President Obama opposed the measure.

After the Magnitsky Act was passed, Putin responded by prohibiting the adoption of Russian children by American families. In his lobbying campaign, Akhmetshin told lawmakers that one way to erase the adoption ban would be to rollback the Magnitsky Act.

Fusion’s role in the campaign was to undercut the narrative about Magnitsky’s prison death and to research Browder, who currently runs the London-based investment firm, Hermitage Capital. Browder filed a complaint with the Justice Department in July laying out the case that Fusion GPS and Akhmetshin are acting as foreign agents of Russia. Foreign agents are required to register with the Justice Department under the Foreign Agents Registration Act.

Grassley has cited Browder’s complaint in his letters to Comey.

For Browder, Simpson’s involvement with Akhmetshin raises questions about the validity of the dossier.

“Glenn Simpson knowingly spread false information on behalf of people connected to the Russian government to try to protect Russian torturers and murderers from consequences,” Browder told TheDC in an interview in January.

“Glenn Simpson’s job was to knowingly and dishonestly change the narrative of how Sergei Magnitsky came to die from murder to natural causes, and to change the narrative that Sergei Magnitsky was a criminal and not a whistleblower,” he added.

Akhmetshin has been a U.S. citizen since 2009, he told Politico last year. He also acknowledged to the website that he was once a Russian counterintelligence officer.

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