Works for me. Unlike impeaching Bush or Cheney, it might lead to a conviction; Gonzales’s perjury before the Judiciary Committees has been just a bit too obvious, even for some of the Republicans.
If Gonzales were impeached and convicted, that would put a crimp in the Administration’s capacity to obstruct justice. And somehow I doubt that the courts would hold still for a claim of executive privilege with respect to testimony needed for the impeachment of the Attorney General.
Update Impeachment, as opposed to a criminal trial, gets around the graymail problem. An impeached official has no right to a public trial. The House Judiciary Committee, or a subcommittee, could review any classified information behind closed doors. Proceedings of the full House cannot be closed to the public, but Members could be invited to read the relevant materials in a secured room. Assuming that Gonzales was impeached by the House, portions of his trial before the Senate could be held in executive session.
In practice, I doubt this matters. Gonzales’s multiple stories about his involvement in the U.S. Attorney firings and the reasons for those firings are probably enough to convict him of perjury, and lots of other laws got bent or broken along the way. Generating an iron-clad impeachment case won’t require using classified evidence. That’s not to say that Gonzales will be convicted; the Republicans might stand firm. But they’d pay for it at the polls.