Updated

Some Democrats in Congress are having a tough time convincing President Obama, as well as their colleagues, to form an independent "truth" commission to probe the evolution of interrogation tactics under the Bush administration.

So lawmakers who oppose those techniques are looking for the next best thing -- the impeachment of one of the authors of the so-called "torture memos."

Jay Bybee, one of the lawyers who wrote the opinions justifying the tactics, is now a federal judge in the 9th Circuit Court of Appeals.

That should change, some Democrats say.

"I think someone who writes a how-to memo on how to break the law should not be a federal judge," said Rep. Jerrold Nadler, D-N.Y.

Democratic Sen. Patrick Leahy, chairman of the Senate Judiciary Committee that gave Bybee a thumbs-up before he was confirmed by the full Senate, argues there never would have been a vote if those memos had been in the record at the time.

"Neither the White House, the Bush administration nor Mr. Bybee gave us the full truth when his nomination was before the Senate," the Vermont senator said. "Had we been given the full truth about what he did, he never would have been confirmed by the Senate. I think both Republicans and Democrats would have voted him down."

Democrats are getting a lot of pressure from left-leaning groups who are after Bybee's hide.

But Republicans seem to be bracing for a fight. Rep. Peter King, R-N.Y., thinks it would be wrong to judge those legal opinions without considering they were written shortly after the Sept. 11 attacks -- when the CIA was trying to track down other Al Qaeda threats against the country.

"I think Judge Bybee should be given a medal for what he did," King said. "But even if I disagreed with those memos, these were memos written in good faith. These are well-written, well-reasoned memos -- people may disagree with them, but he belongs on the bench, he should stay on the bench."

Sen. John McCain, R-Ariz., is on record strongly opposing the techniques used by the CIA, but he thinks it would be wrong to go after Bybee now.

"These people gave their honest opinions even if they were wrong," he told FOX News. "So now we're supposed to investigate them and criminalize them because of their honest opinions? You know, if you went after every lawyer in America who gave bad advice, we'd have pretty crowded dockets."

President Obama on Tuesday opened the door for the possible prosecution of those lawyers who drafted the Department of Justice memos, by deferring to the attorney general on the matter.

Attorney General Eric Holder says only that he'll follow the law in examining the memos, and since Tuesday, Obama has seemed to back away from the calls on the left for a criminal probe.

FOX News' Brian Wilson contributed to this report.