Senate Republican leaders are facing a conservative backlash for their decision to allow an investigation into how memos from Judiciary Committee Democrats ended up in media outlets, with threats of retribution if any GOP staffers face discipline over the matter.

In online columns, e-mail circulations and media interviews, conservative activists late last week began mounting a counteroffensive to try to prevent Judiciary Chairman Orrin Hatch (R-Utah) and Majority Leader Bill Frist (R-Tenn.) from allowing any disciplinary action against the Republican staffers involved in accessing the memos.

“Once again the Republicans seem to be forming a circular firing squad,” said Kay Daly, the head of the Coalition for a Fair Judiciary, the first organization to post the memos in their entirety online. “The Republicans have swallowed the Democrats’ bait, hook, line and sinker.”

In a National Review column published Friday, conservative writer Timothy Carney compared Hatch to Neville Chamberlain, the British prime minister who negotiated with Nazi Germany in the late 1930s, for allowing the probe to go forward in mid-November. Hatch’s action, Carney wrote, “is now acutely damaging to the struggle to get conservative judges onto the federal bench.”

The Committee for Justice, the interest group formed specifically to fight a media war on behalf of President Bush’s nominations, picked up the National Review column and blasted it out to the hundreds of reporters, activists, House and Senate staffers and White House aides on its distribution list. The subject line on the e-mail showed how the group felt about GOP leadership’s actions: “Not good.”

Hatch’s office declined to comment, and Frist’s office also declined to comment on the investigation, which is being headed by Senate Sergeant-at-Arms Bill Pickle. Pickle, who brought in a handful of U.S. Secret Service agents to help with the probe, said last week that he would file a report to Hatch and Sen. Patrick Leahy (D-Vt.), the ranking member at Judiciary, in three or four weeks.

It would be up to Hatch and Leahy to determine whether to make the report public, he said.

The conservative groups are particularly incensed that one of Frist’s top aides is in trouble regarding the investigation and his job status is hinging on the probe’s outcome. Manuel Miranda, Frist’s top aide on judicial nominations who has been the point man with conservative activists on the issue, is on leave “pending the results of the investigation,” Frist’s office said last week.

Miranda has been on leave since about the time of the start of the probe, but Frist’s office first acknowledged that his leave was connected to the probe to The Boston Globe last week.

One conservative strategist familiar with the nomination battles said “any punitive actions of essentially innocent parties, any scapegoating” would be taken by activists as a sign of capitulation to Democrats. This strategist said firing Miranda would be “unforgivable” and seriously hurt Hatch’s legacy as chairman, a run that ends this year.

Daly, who said she did not obtain her copies of the memos from any Hill staffer, said conservatives believe that there was no crime involved since the memos were stored on a server available to both parties. They contend that Hatch and Frist have given up the fight and allowed Democrats to take the offensive.

If Miranda, who has admitted to reading the memos in media interviews but denied distributing them to reporters, faces more discipline or is fired, Daly promised an organized conservative backlash. “The reaction would be incendiary,” she said. “It would be an absolute tragedy. Some very serious discussions will be taking place very soon [among conservatives] about what we are going to do. We’ll decide very soon what we’re going to do about this, but our voices will be heard, make no mistake about it.”