Special counsel John Durham has issued trial subpoenas for members of Hillary Clinton’s 2016 presidential campaign and the Democratic National Committee as he continued to push his theory of a “joint venture” in the case he built against Democratic cybersecurity lawyer Michael Sussmann, who represented Clinton’s campaign.

Clinton’s campaign, the DNC, the now infamous opposition research firm Fusion GPS, and the Perkins Coie law firm are working to resist Durham’s efforts to compel the submission of documents that have been withheld up to this point. The Washington Examiner reported that these groups have argued that claims of attorney-client privilege should keep the records that Durham is seeking concealed.

Durham is continuing to build legal pressure on these groups believing that they coordinated in pushing fraudulent claims that former President Donald Trump colluded with Russia.

Earlier this month, Durham said that Fusion GPS “was not primarily providing or supporting expertise relating to legal advice; instead, it appears that the investigative firm’s primary, if not sole, function was to generate opposition research materials that the firm then shared widely.”

Durham believes that these groups worked together on multiple occasions to set the foundation for the Russian collusion narrative that plagued Trump’s time in the White House.

On Saturday, Durham said, “Meeting to agree on the express goal of a joint venture is precisely what happened here on more than one occasion.”

Durham’s work so far identifies “Tech Executive-1” Rodney Joffe, “Originator-1” April Lorenzen of the information services firm Zetalyitcs, and other researchers began to discuss “searching for and collecting derogatory internet data about the online activities of Donald Trump and his associates.”

In June 2016, Durham argued that Lorenzen “assembled and shared initial purported data” with Joffe, “who, in turn, shared the data” with Sussman.

Durham continued, “The joint venture continued and crystalized in August 2016,” when Sussmann, Joffe, and “agents of the Clinton Campaign” met. Durham pointed to a meeting held on August 12, 2016, where Sussmann, Joffe, Elias, and the co-founder of Fusion GPS met to discuss “the same Russian Bank-1 allegations that the defendant would later bring to the FBI.”

Durham said, “The parties agreed to conduct work in the hope that it would benefit the Clinton Campaign, namely gathering and disseminating purportedly derogatory data regarding Trump and his associates’ internet activities,” Durham wrote. “The evidence will show that as a result of these conversations and during this same time period, Tech Executive-1 did exactly that: he tasked employees from multiple Internet companies and a university working under a pending national security contract to mine and gather vast amounts of internet metadata in order to support an ‘inference’ and ‘narrative’ tying the candidate to Russia.”

Lawyers for Sussmann pushed back against Durham’s subpoenas by calling his actions “overreach” and saying that he “seeks to admit evidence that the law squarely forbids.”