The House Ethics Committee confirmed today that it has extended its contract with the outside investigator who is examining the committee’s botched probe of Rep. Maxine Waters (D-Calif.).

In a joint statement issued by Ethics Chairman Jo Bonner (R-Ala.) and ranking member Linda Sánchez (D-Calif.), the committee announced that it has authorized outside attorney Billy Martin to bill up to $500,000 for work related to the Waters investigation until the new contract expires on July 31, 2012. The probe could end before the contract expires.

The Ethics Committee hired Martin — a partner at the law firm Dorsey & Whitney, whose past clients have included former Sen. Larry Craig (R-Idaho) and other high-profile lawmakers — in July to investigate the actions of committee staffers during the Waters probe and determine how and whether the investigation into the California Democrat could continue.

Martin has billed the committee about $300,000 to date under the terms of the original contract, which was set to expire on Jan. 2.

The committee’s investigation into whether Waters and her staff intervened with federal regulators on behalf of a community bank in which her husband had a financial interest was derailed last November just days before a rare public ethics hearing.

The committee announced at that point that new information had arisen and the trial would need to be postponed; internal documents leaked to the media suggested political infighting within the committee had compromised its investigation.

Martin was charged with first determining whether the committee had mishandled its probe before deciding whether the Waters investigation can continue. At issue is whether committee staffers improperly provided evidence to Members who would be hearing the Waters case.

“To date, Mr. Martin and his team have performed a substantial amount of work to move this matter forward. Mr. Martin has reviewed tens of thousands of pages of documents, interviewed numerous witnesses, and conducted extensive legal research regarding the nature of due process rights that attach to Members of Congress appearing before this Committee,” today’s joint statement said.

A Waters spokesman lamented the speed of the probe and today reiterated that Martin must first determine whether the committee mishandled its investigation before deciding whether its case against the California lawmaker can continue.

“Although disappointed that this matter, which should have been resolved by now, may continue, the only news in today’s announcement is that the investigation into the committee’s misconduct requires more time,” the spokesman said. “The House and the American people should be concerned, as we are, that the extent of the committee’s misconduct and the erosion of Rep. Waters’ due process rights may be so pervasive, that it may take special counsel more than a year to review the extent of the committee’s wrongdoing.”

Ethics was the only committee that was spared a substantial budget cut by the House Administration Committee today, when it backed a resolution to trim total committee spending.

The Ethics Committee budget will increase by 11.5 percent next year, in large part because of the costs associated with Martin’s investigation. Most committees are facing across-the-board 6.4 percent cuts, save for the Armed Services Committee which will absorb only a 2 percent cut.