Lawyers defending AT&T's merger with Time Warner are fighting to make sure their antitrust showdown against the Justice Department stays as public as possible.

U.S. District Judge Richard Leon of the District of Columbia, who is overseeing the DOJ's antitrust case against the merger, said Tuesday that both AT&T and the government's third-party witnesses were “probably” designating too many evidentiary documents and material as confidential. AT&T's lawyer, O'Melveny & Myers partner Daniel Petrocelli, argued the trial should be held in an open courtroom as much as possible.

“It's important that this trial occurs in the light of day,” Petrocelli said.

Opening arguments in the trial, originally set for Wednesday, were pushed to Thursday due to an impending snow storm in Washington, D.C.

Craig Conrath, the government's lead lawyer, said some third-party witnesses need to testify in private but that he planned to make motions a day in advance on behalf of those parties to request the courtroom be sealed.

There had also been some disagreement as to how much of its own material AT&T should be allowed to claim as confidential. Petrocelli said his team agreed prior to Tuesday's hearing to accept the government's position with respect to any confidentiality asserted by AT&T, on the condition that AT&T can raise objections when needed.

“We wanted to clear the path to make it as easy as possible,” he said.

He added, however, that he believed it is unlikely the government's third-party witnesses, many of whom may be employees at AT&T's competitors, really needed to be questioned about confidential information. He said some of the witnesses have an obvious interest in testifying in a closed courtroom, since they would likely want to say how much the merger would hurt them but wouldn't want the public or shareholders to hear that testimony.

He also argued that third-party testimony likely won't rely on financial analysis, but on intuition and experience instead, which can be discussed in public.

The judge agreed that “we know what [third-party witnesses] are going to say,” but stressed that he needed to know how much of what they would say is based on “refined business judgment,” which could likely be discussed in public, versus “mathematical wizardry,” which may involve confidential information.

Conrath said that, for third-party witnesses who will testify about confidential information, it will only make up a small portion of the testimony. He also said that, while it might be in AT&T's interest to keep some of the government witnesses from testifying, it was important that the judge be presented with all the facts.

The judge also said he has a “logistical concern” about repeatedly opening and closing the courtroom and forcing people to leave during the trial, which is expected to last six weeks. He said it's likely that, when witnesses need to be examined in a sealed courtroom, he will have them take the stand at the end of a trial day.

Leon also stressed the burden is on the government's to prove that certain testimony needs to be presented in a sealed courtroom and that he may deny some of the requests, which could potentially hinder the government's argument.

“You can not go into it at all, or you can go into it in public,” the judge said.

The government sued AT&T to block the merger with Time Warner late last year.

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