Michael Sussman was representing the Clinton campaign when in 2016 he passed along information to an FBI counsel. His lawyers say the documents "raised national security concerns" while prosecutors describe them as purportedly detailing a covert channel between a Russian bank and the business of Donald Trump, Clinton's rival at the time.

Sussman was charged with lying to the FBI because he falsely told the counsel he was not providing the allegations to the FBI on behalf of any client despite presenting the information on behalf of the Clinton campaign, prosecutors say.

In a filing in February, Sussman's lawyers moved to dismiss the charge, claiming their client "did not make any false statement to the FBI" but even if he had, "the false statement alleged in the indictment is immaterial as a matter of law."

"Allowing this case to go forward would risk criminalizing ordinary conduct, raise First Amendment concerns, dissuade honest citizens from coming forward with tips, and chill the advocacy of lawyers who interact with the government," the filing stated. "The Special Counsel's unprecedented and unlawful overreach should not be countenanced, and the single count against Mr. Sussmann should be dismissed."

In its reply on Friday, Durham's team urged the court not to follow the demand.