Seventeen members of UC Berkeley’s J-school penned a letter in this morning’s Chron urging journalists and the public to oppose the Justice Department’s attempt to get Chronicle reporters Mark Fainaru-Wada and Lance Williams to reveal their sources in the Barry Bonds steroids case. “This is a case that goes to the heart of much of the investigative reporting done in our country — the type of reporting that exposes corruption and other wrongdoing,” the statement said. “If the government prevails, much of this reporting could dry up, and we would all be the poorer for it.”