"The interior secretary has been asked for documentation for his and his wife's travel."

"Interior Secretary Ryan Zinke failed to properly document his travel, the agency's watchdog said Thursday, preventing it from determining whether he had violated government rules.

Zinke has come under scrutiny for mixing taxpayer-funded travel with political activities, as well as taking military or private planes rather than flying commercial, and the investigation by Interior's Office of Inspector General seeks to clarify whether all procedures were correctly followed.

"Our investigation is delayed by absent or incomplete documentation for several pertinent trips and a review process that failed to include proper documentation and accountability," Deputy Inspector General Mary Kendall said in a letter obtained by POLITICO and first reported by The Washington Post."

Eric Wolff reports for Politico November 16, 2017. [2]