The NYT thinks that it might be

That was the question being debated from Washington to Silicon Valley on Tuesday, after the Justice Department, which has been reviewing the partnership for several weeks, hired Sanford M. Litvack, a veteran antitrust lawyer, to help assess the evidence gathered by its lawyers.

The hiring of an outside lawyer like Mr. Litvack is rare and represents the clearest indication that the Justice Department could be planning to mount a legal challenge to the deal, some analysts said. “They wouldn’t bring in a special counsel unless they were preparing to litigate,” said Sam Miller, a partner at Sidley Austin in San Francisco who acted as a special trial counsel in the department’s first antitrust case against Microsoft…