Michael Sussmann appears in federal court on September 17, 2021.
CNN  — 

Special counsel John Durham gave a glimpse on Wednesday of his extensive use of a federal grand jury to bring a false statement charge against former Hillary Clinton campaign lawyer Michael Sussmann.

In a new court filing, Durham says he issued subpoenas to 15 people and entities in the course of his investigation, including political organizations, a university, researchers, an investigative firm and companies.

Sussmann is only the second defendant in the two-and-a-half-year investigation of special counsel Durham, which previously inspired former President Donald Trump and his supporters to believe a takedown of the FBI was coming for its actions investigating Trump and Russia.

Sussmann is accused of not fully disclosing his motivations and clients – the Clinton campaign and a tech executive – to an FBI official to whom he provided information that suggested a connection between the Trump Organization and Alfa Bank of Russia in 2016.

He has pleaded not guilty.

Durham also said he is beginning to turn over evidence to Sussmann’s defense team so it can prepare for trial. Federal authorities are working to declassify 30 reports of witness interviews, grand jury transcripts and the FBI case file on Alfa Bank – the topic which Sussmann had brought to the FBI in 2016.

Sussmann’s legal team previously asked the court to force Durham to turn over more information to them, in an early stage of the criminal case.

“The grand jury’s detailed, 27-page speaking indictment more than adequately informs the defendant of the charges against him and provides him with sufficient information and facts to prepare his defense at trial,” prosecutors wrote. “Moreover, all or nearly all of the information that the defendant seeks either has already been, or soon will be, made available to him through the government’s discovery.”

CNN has reported Durham issued additional subpoenas after the Perkins Coie lawyer was indicted, indicating Durham continues to investigate.