Zinke, a Stetson-wearing former Montana congressman who has cultivated an image as a rugged outdoorsman, has come under a harsh spotlight in recent weeks for behavior criticized as extravagant for a public official. The agency's inspector general opened an investigation after he ran up bills for travel on chartered jets and mixed business with political appearances, sometimes accompanied by his wife, Lola. It's one of five probes underway of Cabinet secretaries' travel.