Like many of us, Environmental Protection Agency Administrator Scott Pruitt enjoys peace and quiet when he travels and jumps at the chance for a seat upgrade.

Unlike most of us, he does it with federal tax money.

The Washington Post reported this week that Pruitt once spent $1,641.63 on a first-class seat for the 90-minute flight from Washington, DC, to New York City to do a television interview about President Trump’s decision to withdraw the United States from the Paris climate accord. The ticket cost six times as much as the tickets for the two media aides who traveled with him in coach.

He flies regularly in first and business class while his entourage sits in coach, including for international trips he made to Italy and Morocco last year. This week, Pruitt was spotted flying first class again from DC to Boston.

The EPA has cited security as the reason Pruitt springs for more leg room, early boarding, and free drinks. Since taking office, Pruitt has surrounded himself with a 24/7 security detail, built a secret phone booth at the EPA’s headquarters, and swept his office for surveillance bugs.

Pruitt told Bloomberg that these steps were necessary because he faces “unprecedented” threats.

But then he told the New Hampshire Union Leader Tuesday that he flies in first class to avoid uncivil interactions with other travelers.

“Unfortunately, ... we’ve had some incidents on travel dating back to when I first started serving in the March-April timeframe,” he said. “We’ve reached the point where there’s not much civility in the marketplace and it’s created, you know, it’s created some issues and the (security) detail, the level of protection is determined by the level of threat.”

Expensive travel frequently trips up high-profile public employees. Government officials are typically counseled to fly with the lowest-cost airfare to be good stewards of taxpayer money (and to avoid bad optics).

The General Services Administration, which oversees logistics for federal employees, only allows first class travel in specific circumstances, like if a flight is otherwise full or if there is a medical need.

The EPA initially told Politico on Tuesday that Pruitt had a blanket waiver to fly first class, but backed off the claim after Politico on Wednesday pointed out that GSA bans blanket waivers and flights have to be approved on a case-by-case basis. A spokesman instead directed reporters to request information about Pruitt’s travel arrangements formally through the agency’s Freedom of Information Act process, which reporters (including this one) frequently use but has yielded little information during Pruitt’s tenure at EPA.

Meanwhile, ThinkProgress reported Wednesday that the EPA’s in-house watchdog is stretched too thin to expand its probe of Pruitt’s travel habits beyond 2017. The EPA Office of the Inspector General told Congress that it’s too short on staff and budget to expand the investigation.

A taste for luxury flight has already taken down one Cabinet member, former health secretary Tom Price, and there are rumblings about the travel choices of others, including Energy Secretary Rick Perry, Interior Secretary Ryan Zinke, Treasury Secretary Steven Mnuchin, and Veterans Affairs Secretary David Shulkin.

Travel blogger and former Navy officer Richard Kerr noted that the “most common reason that senior [Department of Defense] officials are relieved of their duties continues to be travel fraud.”