“It is entirely possible that he doesn’t use email, but that becomes suspect,” said Justine Cowan, an attorney helping lead the Sierra Club’s legal effort. “How is he conducting business, and is he doing that on purpose so that we don’t get the records? In this day and age, who doesn’t use email?”
https://www.politico.com/story/2018/06/22/scott-pruitt-where-are-his-emails-664285
https://www.politico.com/story/2018/06/22/scott-pruitt-where-are-his-emails-664285