Senate Majority Leader Harry Reid may have broken Senate ethics and Internet rules by using his official website to attack libertarian campaign donors Charles and David Koch, a possible violation of the chamber's prohibition on "partisan" material on members' publicly funded webpages.

The post, titled “The Facts About the Koch Brothers,” was moved from the Nevada Democrat's homepage to a less prominent position on the site Wednesday following inquiries by the Washington Examiner.

The post lists 14 accusations against the Kochs and their businesses, alleging that they pay no corporate taxes, seek to abolish Social Security, pollute the environment and have shady business dealings with Iran. The Kochs are major donors to conservative and Republican causes.

The Senate Rules and Administration Committee strictly bars all "partisan" or political campaign posts on senators' official websites.

Senators posting questionable content can get committee "guidance" or approval but not a waiver from the prohibitions, which have been in place since 2008.

Reid's spokesman did not respond to Examiner questions on whether the majority leader had sought or received such guidance on the Koch post.

Phillip Rumsey Jr., a spokesman for the Senate rules panel, also refused to say whether committee staff had reviewed or approved the Koch post.

Sen. Pat Roberts, R-Kan., the panel's ranking Republican and a member of the Senate Ethics Committee, denounced the post. He also pushed back on Reid’s numerous recent speeches on the Senate floor attacking the Kochs.

“Majority Leader Reid has already demonstrated that he has no problem breaking Senate rules as a means to an end," Roberts told the Examiner. “In doing so, he denigrates his colleagues and the institution of the Senate.“

Rob Walker, former staff director for both the House and Senate ethics committees, told the Examiner that lawmakers must strictly limit website content to “official business" because the official websites are funded with tax dollars.

“Official websites are paid for and supported by official funds,” Walker said. “Official funds are to be used under the terms of which they were appropriated to use for official purposes only. So you can’t use official websites for campaign or partisan political purposes.”

Reid, like most other members of Congress, also has a campaign website that is not publicly funded, and for which there are fewer restrictions on content. Reid's official site, and the sites of other senators, are hosted on the senate.gov web domain.

Cleta Mitchell, an attorney and congressional ethics expert who practices before the Senate and House ethics committees on behalf of Republicans, said Reid's Koch post is “a misuse and abuse of taxpayer money. This is outrageous and definitely a violation of the Senate ethics rules.”

She said “it is not permissible even for an official website to link to a campaign or political website that has material such as this on it.”

Richard Baker, who was the first Senate historian and held the post for 34 years before retiring from it in 2009, told the Examiner that limiting posts on official websites traces back to the pre-digital days when congressmen circulated constituent newsletters at public expense.

“There were regulations back in the glory days of newsletters, an earlier version of a website, where it was produced and sent out at government expenses," Baker said.

"And there were strict requirements there about not overtly promoting members' re-election campaigns and by implication, attacking an opponent,” he said.

The Koch brothers own Koch Industries, which is the second-largest privately held company in the United States.

In addition to supporting a lengthy list of libertarian and conservative candidates and nonprofit groups, the Kochs are also are major philanthropists, contributing hundreds of millions of dollars to humanitarian, medical and artistic causes.

Mark Holden, Koch Industries general counsel, called the Reid post "malicious," as well as "sloppy and unprofessional. The worst-case scenario is that it is intentionally false and misleading information being maliciously published on his official Senate website.”

Melissa Cohlmia, director for corporate communication for Koch Companies Public Sector, condemned the post for alleging that the Kochs paid no corporate taxes.

That claim originated in August 2010 when Austan Goolsbee, former chairman of the White House Council of Economic Advisers, charged in a media interview that the Kochs paid no corporate taxes.

But he recanted the claim in a May 2013 tweet in which he said the claim was a "mistake."

Sen. Chuck Grassley, R-Iowa, said Reid's contention that "Koch is an organized as an S corporation and so pays no corporate-level taxes" is misleading because "no S corporation pays corporate taxes.

"It's misleading to suggest that someone doesn’t pay corporate taxes when the tax structure is organized to pay individual taxes, not corporate taxes," Grassley said.

Last week, Reid's staff drew a line through the text on this particular point, adding, “The Koch’s have issued a statement disputing the claim.”

Cohlmia said the post was also incorrect in claiming that the Kochs advocated for the abolition of Social Security, that their companies are heavy polluters and that a Koch firm sold equipment to Iran.