James Wolfe, 57, pleaded not guilty in federal court Wednesday to charges of making false statements.
Wolfe, the former director of security for the Senate intelligence committee, was arrested last week. Though he's not accused of disclosing classified information, prosecutors say he lied to FBI agents about contacts he had with journalists who covered committee matters.
His lawyers said in a statement that Wolfe served his country for 35 years and never disclosed anything classified or breached the public's trust in him. They said the case raises important First Amendment and media freedom issues that will be addressed in court.
His lawyers also said they expect to file a motion barring federal government officials, including Trump, from making unfair comments about the case.
That was a likely reference to comments Trump made last Friday, when he said the Justice Department had caught "a very important leaker" and that it could be a "terrific thing."
"I'm a big, big believer in freedom of the press," Trump told reporters. "But I'm also a believer in classified information. Has to remain classified."
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