WASHINGTON — Ryan Zinke, the secretary of the Interior Department and a key figure in President Trump’s push to roll back environmental regulations and ramp up oil drilling, is facing increased scrutiny amid federal investigations into allegations that he abused travel spending and maintained close ties with industries he oversees.
The criticism escalated sharply following reports this week that the Interior Department’s Inspector General had referred one of the inquiries to the Justice Department, a potential prelude to a criminal investigation.
The investigations have raised questions about Mr. Zinke’s oversight of the Interior Department, where he is essentially the largest land manager in the United States. He has authority over the nation’s 300 million acres of public lands as well as vast waters off the Atlantic and Pacific coasts and the Gulf of Mexico.
Mr. Zinke faces at least a half-dozen ethics investigations. At least nine other inquiries into alleged ethics violations have been closed, in some cases because Mr. Zinke was cleared, in others because of a lack of cooperation with investigators.
While it is not known which inquiry has been referred to the Justice Department, a person familiar with the matter, who was not authorized to speak publicly, said it was most likely one examining a Montana land deal that involved an organization run by Mr. Zinke’s wife and a development group backed by the chairman of Halliburton, which is one of the nation’s largest companies involved in drilling for oil and gas on public lands.
The inquiries, and the appearance of a financial relationship with a Halliburton executive, “raise the questions of whether you can trust the judgment of someone who appears to be looking to benefit from his public positions,” said Patrick A. Parenteau, a professor of environmental law at Vermont Law School.
Several of the investigations have focused on allegations that Mr. Zinke took steps to either assist his wife, Lolita Zinke, or spent inappropriately on her travel with him. Two weeks ago, a report by the Interior Department’s watchdog office concluded that Mr. Zinke violated agency policy by having his wife travel with him in government vehicles. That report also found that Mr. Zinke considered requesting that his wife become an Interior Department volunteer in order to legitimize her travel.
“He goes everywhere with her,” said Thomas J. Pyle, a Trump campaign adviser who helped the administration develop its energy policy.
Other investigations have delved into policy matters, such as Mr. Zinke’s decision to dramatically shrink the boundaries of the Grand Staircase-Escalante National Monument in Utah. The inspector general’s office is looking into whether the review was conducted in a way that improperly benefited a Republican state representative whose land was removed from the boundaries of the monument.
Mr. Zinke, through his lawyer, has denied any wrongdoing.
Mr. Zinke has emerged as a favorite of President Trump, who has praised his rugged “central casting” persona as well as his role in cutting federal regulations, a centerpiece of the Trump administration’s political agenda. Mr. Zinke has helped lead that charge, wiping out conservation measures, opening up millions of acres of land and water to energy exploration and in the process remaking the landscape of the American West.
Mr. Zinke has promoted policies aimed at opening the east coast to offshore oil and gas drilling for the first time, loosening the standards of the Endangered Species Act, weakening safety regulations for offshore drilling equipment and shrinking the boundaries of national monuments to open the land to mining and drilling.
Moves such as these have brought Mr. Zinke into Mr. Trump’s favor. In an administration noted for its policy swings and turnover — numerous campaign and administration officials have been convicted or pleaded guilty to crimes, while others have resigned amid allegations of ethics violations — Mr. Zinke has delivered a steady string of substantive policy accomplishments.
Mr. Zinke was a one-term congressman from Montana when Mr. Trump tapped him to run the Interior Department. He was considered a surprise choice but had reportedly gained favor with Donald Trump Jr., because, like the President’s son, he is an avid game hunter.
Over the past decade or so, Mr. Zinke has pursued dual careers as a politician and businessman. Some of his business dealings in that time formed relationships with individuals and industries that would become relevant in later years in his role as secretary of the interior. For instance, he was a director of a nonprofit group that pushed to develop Montana’s drone industry by using the state’s big open spaces as a testing ground.
At the Department of Interior, under Mr. Zinke’s leadership the agency has planned to increase its use of drones, particularly for fighting wildfires. Mr. Zinke’s personal experience with the drone industry and ties to a number of stakeholders in the business come from having co-founded the Center for Remote Integration, the nonprofit organization that promoted their use.
In August 2017, Mr. Zinke wrote to his chief of staff expressing interest in his agency’s plans for drone use. “I want to see the drone contract before the award,” he wrote, according to emails released in response to public records requests and highlighted by Center for Western Priorities, a conservation organization.
Richard W. Painter, a White house ethics lawyer under George W. Bush who has been critical of the Trump administration, said it struck him as unusual that such a contract would be significant enough to reach Mr. Zinke. “It better be a really important contract to rise to the level of a cabinet secretary,” he said.
From the partly redacted email, it is unclear which contract Mr. Zinke had sought.
Heather Swift, a spokeswoman for the Interior Department, said Mr. Zinke “asked to see the requirements of the request to ensure the description of services and capabilities met the highly-specialized needs of the Department.” She said that use of the technology “is supported by both parties in Congress” and that Mr. Zinke “had no role in awarding contracts.”
In May 2018, Mr. Zinke announced a round of contracts for drone services to assist in fighting wildfires. One of the contracts was awarded to a company called Insitu, a Boeing subsidiary with past ties to Mr. Zinke’s efforts on behalf of the industry.
Aaron Weiss, the spokesman for the Center for Western Priorities, the conservation organization, said Mr. Zinke’s interest in drones is an example where “he has not drawn a bright line with his career prior to Interior.”
In an email, Monica Golden, a spokeswoman for Insitu, said the company had won hundreds of contracts since the early 2000s, and “anyone who has had significant interest in this space over that time period almost certainly would have found us through one avenue or another.” She said the company’s services had been used in two huge fires this year in Oregon and California.
In April 2017, Mr. Zinke and several members of his staff at the Interior Department participated in a meeting that included executives from Proof Research, a Montana-based firearms company, according to Mr. Zinke’s calendars, a meeting reported by Huffington Post. About six years ago, Mr. Zinke reported income from the company, which used a different name at the time, a 2014 disclosure showed. He did not disclose in financial filings that he retained a small stake in it.
Mr. Zinke, in his 2018 financial disclosure, noted his interest, valuing it at less than $1,000. Ms. Swift of the Interior Department said the amount fell “well under the threshold” for reporting, but Mr. Zinke added it to demonstrate “he has nothing to hide.”
In another role, Mr. Zinke served as a board member for a Santa Barbara company called Save the World Air, now known as QS Energy, which develops technology for oil and fuel delivery systems. In 2012, Mr. Zinke traveled with the company’s president, where they worked to introduce the company’s oil pipeline efficiency technology to “various members of the North American energy industry,” according to a news release announcing his appointment.
Ms. Swift said Mr. Zinke “has had no contact with anyone from the organization to his knowledge” in his current job.
The episode that has garnered the most criticism was Mr. Zinke’s discussions about a land deal involving an organization run by his wife, Lolita Zinke, and the Halliburton chairman.
In June, the Interior Department’s Inspector General opened an investigation into whether conversations Mr. Zinke had with David J. Lesar, the chairman of Halliburton, about a Montana land deal constituted a conflict of interest.
Politico first reported the deal, in Mr. Zinke’s hometown, Whitefish, Mont., which involved a development group backed by Mr. Lesar and a charitable foundation established by Mr. Zinke and headed by his wife. It included a hotel, retail shops and a microbrewery.
The examination of “involvement in and use of taxpayer resources to advance land developments” focuses on whether taxpayer money was improperly spent on Mr. Zinke’s travel when he met with Halliburton representatives.
Ms. Swift has said the secretary did nothing improper and that he had resigned from his foundation’s board of directors before the deal was made.
Coral Davenport reported from Washington, and Steve Eder from New York.
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