Former cybersecurity chief Christopher Krebs says he was defamed by the Trump campaign and attorney Joseph diGenova.

UNITED STATES – MAY 14: Christopher Krebs, director of the Department of Homeland Security’s Cybersecurity and Infrastructure Security Agency, testifies during a Senate Judiciary Committee hearing in Dirksen Building titled “5G: National Security Concerns, Intellectual Property Issues, and the Impact on Competition and Innovation,” on Tuesday, May 14, 2019. (Photo By Tom Williams/CQ Roll Call)