WASHINGTON—Eleven pages of State Department documents released on Jan. 7 in a Freedom of Information Act (FOIA) lawsuit filed by Judicial Watch show that Jonathan Winer, an assistant to then-Secretary of State John Kerry, used his private email address to convey information he received from former British intelligence officer Christopher Steele to top U.S. diplomatic officials. “I will send them to her [his assistant, Nina Miller] from my non-State email account, not copying myself,” Winer said in response to a December 2014 email from Paul Jones, principal deputy assistant secretary for European Affairs. Jones wanted Winer to use the State...