– A congressional inquiry of U.S. Rep. Michele Bachmann has been referred to the House Ethics Committee, significantly raising the stakes in the Minnesota Republican’s efforts to fend off questions about her 2012 presidential campaign’s financial dealings.

A report issued Tuesday by the independent Office of Congressional Ethics (OCE) shows that its bipartisan board sent all seven cases before it last month to the House Ethics Committee, meaning they found “substantial reason” to believe they all involve potential ethics violations.

Among the cases known to be pending before the board was a probe of potential campaign finance violations by Bachmann as well as allegations that she took members of her campaign staff on a book tour to promote her personal political memoir, “Core of Conviction.”

Under rules set forth for the ethics board, there was no public disclosure Tuesday of the individual cases transmitted for further review by the House ethics committee. Instead, the report included a general summary of the board’s actions showing that it did not dismiss or terminate any cases in the past three months, the same period that Bachmann has been under investigation.

William McGinley, a Washington attorney for the Bachmann campaign, disputed the suggestion that none of the allegations against her were dropped, although he didn’t say what claims the OCE might have referred for dismissal.

He also criticized the OCE report — a routine quarterly report of its activities — for exposing Bachmann indirectly to unfair publicity.

“Today’s OCE disclosure not only is factually inaccurate, but is a shameful publicity stunt that undermines the confidentiality provisions designed to protect members of Congress from undue prejudice,” he said. “We are grateful that this matter is finally in the hands of the fair-minded and capable professionals at the House Committee on Ethics who we are confident will dismiss all allegations in this matter.”

OCE spokeswoman Kelly Brewington said the agency did not disclose the identities of any of the lawmakers under review.

“The OCE’s quarterly report is a regular, anonymous statistical summary of OCE activities that has been a component of the office’s transparency for the last five years,” she said. “The report is accurate and does not identify any subject of any OCE review and in no way deviates from any other quarterly report OCE has released since our inception.”

The ethics board has often faced criticism from lawmakers since it was created by Congress in 2008. But the board does not have the authority to levy sanctions. That power is reserved for the ethics committee, which faces a deadline later this month to state publicly whether to proceed with the board’s latest referrals, including the one on Bachmann.

Sources who have been interviewed by the OCE have told the Star Tribune that investigators focused on Bachmann’s 2011 book tour, which spanned from Minnesota and Iowa to the East Coast. Federal election and House ethics rules generally forbid candidates from using campaign funds or resources to sell or promote their own books, which are considered personal business activities.

Unlike potential campaign finance violations, which could involve top officials in Bachmann’s campaign, the book tour allegations focus on Bachmann’s personal conduct in selling her book.

Among those questioned in the probe was former campaign staffer Barb Heki, an Iowa woman who recently settled a lawsuit against Bachmann over allegations that her campaign misappropriated an e-mail list of Iowa home-school families. She’s one of several paid Bachmann campaign staffers who reportedly took part in at least one book tour event.

The book tour inquiry represented a sharp escalation of the OCE probe, which started in February as an inquiry into allegations of campaign finance violations brought by whistleblower Peter Waldron, a Florida minister who worked for the campaign. Waldron alleged that the campaign improperly used Bachmann’s independent political organization, MichelePAC, to make undisclosed payments to several top officials for campaign work. Those allegations also are being investigated by the Federal Election Commission and the FBI.

It remains unclear, however, what action the House Ethics Committee might take, given Bachmann’s decision in late May not to seek a fifth term in Congress. Generally, the panel, made up of an equal number of Democrats and Republicans, can push back a decision on whether to impanel an investigative subcommittee to pursue the allegations, or dismiss the case altogether.

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