Department of Interior has itself been hit by claims of corruption - and scandal over years of persistent sexual

ethics prone over claims she ran campaign operations out of her government office

But she is the subject of an

Donald Trump's frontrunner to lead the scandal-plagued Department of the Interior is a congresswoman currently under a House ethics investigation for misusing government funds.

Cathy McMorris Rodgers, a Republican Congresswoman, is at the top of Trump's short list for secretary of the Department of the Interior, sources close to the transition told the Dailymail.com, and could be announced as soon as Friday.

But as the subject of an ongoing ethics probe, McMorris Rodgers's appointment could complicate Trump's election promise to 'drain the swamp' in Washington D.C.

Congressional investigators have been looking into allegations the 47-year-old congresswoman from Washington state ran campaign operations out of her government office and sent aides to campaign events on the taxpayer dime.

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Cathy McMorris Rodgers, a GOP congresswoman from Washington state, is expected to be President-elect Donald Trump's pick for Interior Secretary. Together they're pictured above in November at the clubhouse of Trump National Golf Club in Bedminster, New Jersey

Questions: Cathy McMorris Rodgers (right) is being investigated over ethics code violation allegations

The probe was launched nearly three years ago, and although investigators have stayed tight-lipped on the matter, sources confirmed that it remains open.

The investigation could be hurdle to a Senate confirmation, particularly since lawmakers have raised concerns about a string of recent corruption, sexual harassment, and nepotism scandals at the Department of the Interior.

But it could be a double-victory for McMorris Rodgers if she's appointed. The House Ethics Committee often shelves its investigations into lawmakers if they leave congress before the cases are resolved.

In 2014, a separate congressional oversight office looking into the case found 'substantial reason to believe that Representative McMorris Rodgers used congressional funds, staff, and office space for campaign activities.'

According to the Office of Congressional Ethics report, McMorris Rodgers blurred the line between her congressional office and campaigns for reelection and Republican leadership between 2010 and 2012.

The office found indications that her House aides did campaign work on the government clock, including traveling for campaign events and a trip to the 2012 Republican National Convention.

She also allegedly used House office space and resources for debate prep and videos, and used a paid campaign consultant to help her get ready for congressional media appearances.

McMorris Rodgers told investigators that she did have a campaign debate prep meeting at her congressional office because she was worried her home would be too noisy due to her children.

She has denied knowledge of any wrongdoing and said her aides were responsible for managing the firewall between her House and campaign work.

The Department of Interior has hit by claims of corruption, with female employees coming forward to report persistent sexual harassment at Grand Canyon National Park (pictured)

The ethics office recommended the case to the House Ethics Committee, which took over the probe in early 2014.

The committee has declined to publicly address the case, and a spokesman told the Dailymail.com that he had 'no comment.'

At least one former McMorris Rodgers aide has spoken out publicly about the probe, claiming that he faced retribution from McMorris Rodgers and her close aides for cooperating with investigators.

The staffer, Todd Winer, said the congresswoman 'defamed' him in the media by planting stories that suggested he made up stories of wrongdoing by McMorris Rodgers because he was disgruntled after being fired.

'[McMorris Rodgers's] work to expose, slander, and intimidate a cooperative witness in a Congressional investigation is an unprecedented abuse of power,' Winer wrote in an open letter to media outlets in 2014, published in Roll Call.

'In addition, CMR has violated numerous Congressional rules, lied about those violations, and worked to cover them up. That will become crystal clear as the Ethics Committee continues its work.'

Winer also said the House Ethics Committee was investigating his allegations of reprisals, and claimed there is evidence McMorris Rodgers and aides lied to Office of Congressional Ethics investigators.

He did not respond to an emailed request for comment or phone calls to a listed number.

A spokesperson for McMorris Rodgers did not respond to request for comment.

Her potential appointment has already sent her colleagues vying to replace her as head of the House Republican Conference, a senior GOP leadership position, Politico reported on Thursday.

The Department of Interior (one of their signs pictured above at Wee Thump Joshua Tree Wilderness) is in charge of the management and conservation of federal land and natural resources

The Department of the Interior has been plagued by scandal over the past year, prompting the House Committee on Natural Resources to hold a hearing on the department's 'culture of corruption' last May.

Female employees recently came forward to report persistent sexual harassment by male staff at the Grand Canyon National Park, saying they have been groped, propositioned for sex, and photographed up their skirts.

One top official was also caught giving jobs to friends and relatives, and another recently published an outside book in violation of ethics rules.

Another senior official with the U.S. Fish and Wildlife Service was recently caught spending $96,000 in government money on personal travel, and was paid $400,000 by an outside group that receives grants from his office.

Ethics questions were also raised after the department was forced to shutter an geological lab in Colorado last spring, amid reports that analysts had intentionally manipulated environmental and energy data for decades.

The inspector general for the Department of the Interior referred 29 cases of alleged criminal misconduct to the Justice Department last year, although Republicans criticized the law enforcement agency for only prosecuting 12 of those cases.

Senior leaders at the Department of the Interior are accused of turning a blind eye to misconduct within the agency.

The department's top oversight official told congress earlier this year that she was 'continually surprised by the variations of misconduct brought to our attention,' adding that 'management avoids discipline altogether' by transferring problem employees to other positions.