WASHINGTON — The staff of U.S. Rep Marty Meehan wiped out references to his broken term-limits pledge as well as information about his huge campaign war chest in an independent biography of the Lowell Democrat on a Web site that bills itself as the “world’s largest encyclopedia,” The Sun has learned.

The Meehan alterations on Wikipedia.com represent just two of more than 1,000 changes made by congressional staffers at the U.S. House of Representatives in the past six month. Wikipedia is a global reference that relies on its Internet users to add credible information to entries on millions of topics.

Matt Vogel, Meehan’s chief of staff, said he authorized an intern in July to replace existing Wikipedia content with a staff-written biography of the lawmaker.

The change deleted a reference to Meehan’s campaign promise to surrender his seat after serving eight years, a pledge Meehan later eschewed. It also deleted a reference to the size of Meehan’s campaign account, the largest of any House member at $4.8 million, according to the latest data available from the Federal Election Commission.

“Meehan first ran for Congress in 1992 on a platform of reform,” the pre-edited entry said. “As part of that platform Meehan made a pledge to not serve more than four terms, a central part of his campaign. This breaking of the pledge has been a controversial issue in the 5th Congressional District of Massachusetts.”

The new entry reads in part: “Meehan was elected to Congress in 1992 on a plan to eliminate the deficit. His fiscally responsible voting record since then has earned him praise from citizen watchdog groups. He was re-elected by a large margin in 2004.”

Vogel said, “It makes sense to me the biography we submit would be the biography we write.”

The change doubled the length of the entry on Meehan, corrected errors and replaced “sloppy” writing, Vogel said. “Let the outside world edit it. It seemed right to start with greater depth than a paragraph with incorrect data from the ’80s.”

Wikipedia’s online honor system has made it ripe for abuse by vandals. Recently, a user wrote in a Wikipedia bio that Virginia Congressman Eric Cantor “smells of cow dung.” Another wrote that Senate Majority Leader Bill Frist is “ineffective.” These statements were traced to the House Internet-protocol (IP) address.

In November and December, The Sun has learned, users of the House’s IP address were temporarily blocked from changing content because of violations described by the site as a “deliberate attempt to compromise the integrity of the encyclopedia.”

“I’m not denying it,” Jon Brandt, a spokesman for the Committee on House Administration, which oversees the House computer network, said when asked to confirm House ownership of the address.

For security reasons, Brandt declined to say to whom the address is assigned.

While vandalism is a problem, deleting factual information raises ethical concerns, said Geoffrey Bowker, director of the Center for Science, Technology, and Society at Santa Clara University.

“The vandalism is just plain childish,” Bowker said. “The term-limit pledge (that was changed by Meehan’s staff) is a much more serious case. That’s someone trying to alter the public record.

“To knowingly remove a truthful statement is just wrong,” he added. “It’s not the place of any special-interest group to tamper with the facts available to the public.”

Most of the 1,000 House changes were meant to enhance various encyclopedia entries. Slurs against Cantor and Frist, which have been removed, are the first examples of abuse that Wikipedia’s founder Jimmy Wales has seen derived directly from the legislative branch of the U.S. government.

Wikipedia records every change to its site and who made it. The encyclopedia prefers that editors log in with a user name, but it’s not necessary. Many editors make changes anonymously; Wikipedia identifies these users by tracking the number assigned to their Internet entry point, called an IP address.

But Wales said the deletion of factual information goes against the principles of Wikipedia, which promotes a “neutral point of view” policy.

“You don’t delete it,” Wales said. “If they wanted to put in their side of things, that would seem ethically relevant, rather than just omitting it.”

Mistakes were inserted into the Meehan entry at different points of its evolution, according to an examination of the edits. One editor erroneously said Meehan attended Harvard College; another indicated it is likely that Meehan would run for Sen. Edward Kennedy’s seat.

Wikipedia reaches around the globe, having 3.1 million articles published in more than 200 languages. The English-language version is the largest category, with more than 910,000 articles and 856 million words. That’s more than six times larger than Encyclopedia Britannica — the largest reference printed in English.

And people read it.

Yesterday, Wikipedia was ranked the 19th- busiest site on the Internet, according to alexa.com, a subsidiary of Amazon.com that tracks Webtraffic.

A new reference to Meehan’s term-limit pledge was inserted in the Wikipedia entry in November by a person not using the House address.

On Dec. 27, someone using the House IP address reduced the reference to a single sentence: “(Meehan) also supported term limits, pledging to serve no more than four terms.”

Vogel said he did not authorize the change.

No reference to Meehan’s top-rated campaign account has been reintroduced.

The changes by Meehan’s staff are not as “reprehensible” as inserting derogatory comments in someone else’s entry, said Stephen Potts, former director of the federal Office of Government Ethics, which establishes conduct standards for the executive branch.

But the sheer breadth of changes emanating from the House reflects an abuse of public time and equipment, said Potter, now chairman of the Ethics Resource Center.

“That kind of usage, plus the fact that they’re changing one person’s material, is certainly wrong and ought to be at a minimum the focus of some disciplinary action,” he said.

Evan Lehmann’s e-mail address is elehmann.com.