Interior Secretary Ryan Zinke violated government travel policies by bringing his wife along on taxpayer-funded trips and asked staff to explore making her a department volunteer, a move that would have legitimized her travel, according to a new report by the agency’s internal watchdog.

The months-long investigation by the agency’s Office of the Inspector General looked into multiple allegations that Zinke had abused his position. It determined that, despite rules against it, Interior Department staff signed off on Zinke’s wife, Lolita, and others joining him in government-owned vehicles.

The investigation also found that the Department of the Interior spent $25,000 to send a security detail with Zinke and his wife when they vacationed in Turkey and Greece but that doing so did not break any rules.

Zinke told investigators that all requests for Lolita to travel with him were approved by agency ethics officials and that she never rode in a government vehicle without him. An unidentified employee at the agency’s solicitor’s office said she “routinely advised Secretary Zinke’s schedulers that DOI policy prohibited his wife’s presence in Government vehicles and that it would be ‘cleanest’ and ‘lowest risk’ if she did not ride with him, but she also told schedulers that she could justify Lolita Zinke riding in a Government vehicle because Secretary Zinke could not use a personal vehicle for travel,” according to the report.

In July, after learning of the investigation, the department updated its travel policy to allow for family members to travel with the secretary in federal vehicles.

The report also details how Zinke asked department employees to research the “legal and ethical implications” of making his wife an official volunteer of the agency, even an ombudsman for veterans, and was “upset” that she had to pay her way during their trips. Ed McDonnell, an alternate designated agency ethics official, provided investigators notes he took during a June meeting with Daniel Jorjani, the principal deputy solicitor, which “said that in response to a news article about Lolita Zinke’s traveling with her husband, Secretary Zinke had told Jorjani to tell the media that his wife was an ombudsman for the DOI, but Jorjani responded that they could not say that.”

McDonnell said he voiced concerns about accommodating Lolita Zinke, the report notes.

“We’re spending taxpayer dollars trying to figure out if she can be a volunteer so that he [Zinke] doesn’t have to pay” reimbursement for her travel, McDonnell said.

Zinke denied that his request to make his wife a volunteer was an attempt to pin her travel costs on taxpayers. Ethics officials ultimately advised Zinke that, although making her a volunteer would not violate rules, “the optics were not good, so they decided against it,” the report states.

The Interior Department did not immediately respond to HuffPost’s request for comment. But in a statement to Politico and other news outlets, agency spokeswoman Heather Swift said the report “proves what we have known all along: the secretary follows all relevant laws and regulations and that all of his travel was reviewed and approved by career ethics officials and solicitors prior to travel.

“Additionally, the secretary received the same exact legal advice from the solicitors as previous secretaries and he acted consistently. The report even said so.”

Conservation groups were quick to slam Zinke. Kate Kelly, public lands director at the left-leaning Center for American Progress and a former Interior Department official in the Obama administration, said in an emailed statement that the report “is not a good look for Ryan Zinke, painting a picture of a Secretary inclined to twist rules for personal gain.” And Jen Rokala, executive director of the Colorado-based Center for Western Priorities, said it showed Zinke’s “dogged determination to use his office for personal gain, even going so far as to tell Interior’s top lawyer to lie to the public to justify his wife’s travel.”

“Secretary Zinke owes the American people an apology — and a refund,” Rokala added.

The report comes amid a bizarre controversy surrounding Interior’s inspector general’s office. The Hill and other media outlets reported this week that a Trump political appointee at the Department of Housing and Urban Development, Suzanne Israel Tufts, was set to take over Interior’s internal watchdog role. But Swift denied the story on Thursday, saying that the media had jumped to conclusions.

“Ms. Tufts is not employed by the Department and no decision was ever made to move her to Interior,” Swift said in a statement to BuzzFeed and other outlets. She added that an email HUD Secretary Ben Carson sent to staff “had false information in it.”

Much like former EPA Administrator Scott Pruitt, Zinke has been unable to steer clear of negative headlines. He has faced at least 18 formal investigations ― many of them ongoing ― and calls for several others. That’s more than the last four interior secretaries combined, according to an analysis by the Center for Western Priorities.