Eight House Members who face a preliminary review by the Office of Congressional Ethics could find out as early as this week whether the probe will end, but the source of the investigation is unlikely ever to be revealed.

The OCE, which reviews potential rules violations and refers investigations to the House Committee on Standards of Official Conduct, is not required to identify the spark for its investigations, be it a tip, informant or newspaper article.

The OCE has neither confirmed nor denied whether it is reviewing Members who held fundraisers in December 2009 or any aspect of the financial reform legislation approved in the House that month.

But each of the eight Members — Reps. John Campbell (R-Calif.), Frank Lucas (R-Okla.), Chris Lee (R-N.Y.), Joe Crowley (D-N.Y.), Jeb Hensarling (R-Texas), Mel Watt (D-N.C.), Tom Price (R-Ga.) and Earl Pomeroy (D-N.D.) — confirmed the inquiry in either public statements or press reports last week.

Based on OCE letters to Members and lobbyists dated as early as May 24, some lawmakers could find out as early as this week — when the first 30-day period may expire — whether the query will be dropped.

According to those lawmakers, one of whom described the review as an “audit,” the probe is in its initial 30-day stage. If the OCE opts to close the matter in that period, it will not release a public report, although Members would be privately informed of that decision. If the investigation continues to its second phase, however, the OCE must refer a report to the ethics committee recommending a formal dismissal or further review.

Although the OCE accepts complaints from the general public, the office does not actually have a formal grievances submission process. House Members balked at the notion when the chamber established the OCE in March 2008 over concerns that a formal process would be used for political gamesmanship.

The House ethics committee does use a formal complaint process, but only Members may file a grievance.

At the time of the OCE’s creation, Rep. Mike Capuano (D-Mass.), who chaired a panel tasked with designing the ethics office, suggested instead that the OCE would rely on receiving tips “over the transom” or from newspaper items.

But those initial sources are not made public. In the 15 public reports that the OCE has released to date, the office has not identified the origin of its work.

Instead, the reports note the date that the OCE begins a “preliminary review” at the request of two of its board members. The board, chaired by ex-Rep. David Skaggs (D-Colo.) and co-chaired by ex-Rep. Porter Goss (R-Fla.), comprises six former Members, a former House officer and a former Federal Election Commission aide.

Although the allegations in those 15 reports, as well as other reviews the OCE has conducted that have been dismissed before a formal report was made to the ethics committee, sometimes appear to be tied to a publicly available complaint or report, there is no way to verify the source.

Among the published reports, one investigation focused on lawmakers’ ties to the now-defunct PMA Group, which followed reports that FBI agents raided PMA’s office in late 2008.

Similarly, the OCE examined whether ex-Rep. Nathan Deal (R) sought to persuade Georgia officials to preserve a state-funded auto salvage program that benefited his family’s business following reports in the Atlanta Journal-Constitution in early 2008. Deal, who left Congress before the House ethics committee ruled in the matter, has denied wrongdoing.

The OCE also examined allegations in March 2009 that five House lawmakers violated the chamber’s rule on privately funded travel when they accepted trips to a Caribbean conference. Reports by the New York Post and the conservative National Legal and Policy Center raised questions over the trips several months earlier. The House ethics committee later ruled the trips had violated House rules, although it did not hold the Members responsible, with the exception of Rep. Charlie Rangel (D-N.Y.), whose staff was aware of the conflict.

OCE investigators also recently closed their review of whether five House lawmakers received an improper gift in the form of below-market rent at a Capitol Hill townhouse, an inquiry apparently sparked by a request from the ethics watchdog group Citizens for Responsibility and Ethics in Washington.

Since that probe closed after the initial review period of 30 days, the OCE is not required to issue a formal report to the ethics committee, and no public report will be released. But each of the five lawmakers received private letters informing them of the investigation’s end.

An OCE spokesman declined to comment for this article, but the office addressed its use of newspapers and anonymous tips in an October report, issuing a statement that it does not initiate reviews based solely on those sources.

“The OCE Board notes that in all cases before deciding to authorize a preliminary review it exercises reasonable due diligence to determine that objectively verifiable facts exist to substantiate an allegation and that the standard of proof set out in its Rules is met, namely, that a ‘reasonable basis’ exists to believe an allegation,” the OCE stated in a quarterly report. “Such a determination does not constitute a finding that a violation has actually occurred. The OCE Board has never authorized a review based on an anonymous ‘complaint’ or a newspaper article,” the report continued.

Nonetheless, there is no prohibition on the OCE conducting its own research into Members, nor is the House ethics committee barred from doing so.

Both the OCE and House ethics panel are permitted to open inquiries without a formal complaint.

Cleta Mitchell, an attorney with Foley & Lardner who has represented a House lawmaker investigated by the OCE and is critical of the office’s procedures, said investigators are unlikely to find a violation of the chamber’s rules or laws in the case of the eight Members, unless a lawmaker actually agreed to a quid pro quo.

“They’ve looked at the FEC reports of Members who received contributions from certain types of industries around the time of the financial services vote,” Mitchell said. “That’s it. That’s not a violation of anything.”

Although the House Ethics Manual directs Members to “avoid the appearance” of conflicts when fundraising — and reminds lawmakers that extortion is illegal — there are no prohibitions on the timing of fundraisers near votes.