U.S. District Judge Emmet Sullivan told the court before the jury arrived that he knew "exactly" what he saw, CNN reported Tuesday.
Sullivan was referring to courtroom conduct Monday by defense attorney Robert Bundy, who represents Bill Allen, the former Alaskan energy company executive who was back on the stand Tuesday.
Stevens, R-Alaska, pleaded not guilty to charges that he failed to report more than $250,000 in gifts and house renovations on Senate financial disclosure forms. Allen's now-defunct energy services firm did the renovations.
"I couldn't believe what I was seeing," Sullivan said of Bundy in the courtroom Monday. "The thought occurred to me -- that's borderline obstruction of justice."
"I didn't do a g------ thing," Bundy told CNN outside the courtroom Tuesday.
Defense attorney Brendan Sullivan filed more documents to his motion to dismiss the case against Stevens, the longest-serving Senate Republican who is seeking re-election, The Hill reported. The motion alleges the government sat on evidence that could have been beneficial to Stevens's defense.