A nonpartisan clerk working for House Judiciary Committee Democrats inadvertently publicized the e-mail addresses of tipsters to an electronic Web site established by Democrats to aid in gathering information about the U.S. attorneys scandal.

A statement from the Judiciary Committee released on Monday evening clarified that the accidental e-mail was the result of a “user error” rather than a technological one and apologized to the tipsters while promising to support them in any bid for legal protection.

As first reported on the Talking Points Memo and Daily Kos Web sites, the committee sent an Oct. 26 e-mail to more than 150 tipsters explaining that the deadline for submitting tips was 11:59 p.m. Oct. 30. It also allowed tipsters three days to withdraw their e-mails rather than have them reviewed by the committee.

The problem: The sender left the e-mail addresses of the recipients visible, potentially compromising their identities. A “substantial number” of e-mail addresses appear to contain proper names, the committee said.

“You are among the people who have submitted e-mails to the U.S. House Judiciary Committee on its Web site tip line for Department of Justice employees to report allegations or concerns regarding possible wrongdoing involving the department,” the Judiciary e-mail stated, according to TPM.

Ironically, the e-mail described the stringent security measures designed to protect the information, explaining that only a full committee vote could authorize “broader disclosure” of an e-mail in consultation with the tipster.

A Judiciary Committee spokeswoman declined to reveal the identity of the staffer. It is unclear how the tips will now be handled.

“The Committee apologizes for the concern this error may have caused, and is making every effort to protect the confidentiality of those who chose to provide information on the tip line,” a spokeswoman said in a statement.

“Any whistleblowers who sent in tips to this website are entitled to full legal protection. We are determined to ensure that they receive that protection and are taking steps to further that objective.”

The e-mail snafu is embarrassing for committee Democrats, led by Chairman John Conyers (Mich.), who have ceaselessly bashed the Justice Department over its inept handling of the firing of nine prosecutors in 2006. Much of the information Democrats gathered against Justice Department officials was through reams of revealing e-mails.

But Judiciary ranking member Lamar Smith (R-Texas), who has criticized the Justice Department probe as an “endless piscine expedition,” was low-key in his criticism on Monday.

“I am very concerned by the report, but we are still gathering all the facts. So I will reserve comment,” Smith said.

Brian Kennedy, a spokesman for House Minority Leader John Boehner (R-Ohio), however, was more direct.

“If they [tipsters] face retaliation or other negative consequences, they have no one else to blame but the committee itself.”

The Justice Department, which would not confirm whether anyone in the department had seen the e-mail, said the mistake illustrates why delicate investigations should be handled internally.

The probe should be “left to the [Justice] Office of Inspector General or the Office of Professional Responsibility,” Justice spokesman Brian Roehrkasse said. There are “well-established mechanisms in place for dealing with sensitive whistle-blower investigations.”

Deputy Inspector General Paul Martin had not seen the e-mail either on Monday, he told Roll Call.

Neither had the office of Vice President Cheney — whose public address (vice_president @whitehouse.gov) was included in the blast missive.

“I haven’t seen it. The vice president hasn’t seen it,” spokeswoman Megan Mitchell said Monday afternoon.

The committee confirmed that Cheney’s e-mail was on the list as the likely result of a prank. But that didn’t stop wild conspiracy theories from running rampant on the Web. Bloggers speculated that Cheney had intentionally sabotaged the tip line as part of the Bush administration’s aggressive electronic surveillance initiative.

“Remember, these guys are up against the data sweeping of everything!” wrote “Paranoid Yet?” on the TPM site.

The committee established the Web form to collect tips on June 20. But following complaints from Republicans that they should get access to it, the House Parliamentarian agreed that access to the e-mails’ contents should be restricted until a bipartisan agreement was brokered.

On Oct. 24, the committee voted on a bipartisan resolution regarding the handling of the confidential data, including language directing a committee staffer to advise the tipsters of the “changed conditions for access.”

Thus, the aide created two distribution lists — “Right Justice” and “Right Justice 2” — in Microsoft Outlook. The staffer relayed that there was a box marked “private” in the Outlook distribution function and “mistakenly believed” that would prohibit the sharing of e-mail addresses. The employee said only the distribution list name was included in the “To” field.

“This was an inadvertent clerical error, and contrary to speculation, not the result of ‘hacking’ or any malicious act,” the committee spokeswoman said.

“As a result of this mistake, all e-mail addresses of all recipients were visible to everyone who received the email. No further information or content of any of the e-mails was revealed,” she added.