Secretary of State Rex Tillerson could soon be called to testify about a separate email account he used for years to discuss global warming while he served as CEO of ExxonMobil. That’s according to the Associated Press, which reports that New York Attorney General Eric Schneiderman is prepared to question Tillerson as part of his probe into whether Exxon misled its investors about the impact of climate change. While at Exxon, Tillerson used the alias “Wayne Tracker” on a separate email account to discuss climate-related topics. Exxon officials have admitted that most of the emails from the account have been permanently deleted and that the company allowed months’ worth of Tillerson’s emails to be deleted even after the New York Attorney General’s Office requested they be preserved.