Lipton joined "The Times" in 1999, covering the final years of the administration of New York Mayor Rudolph W. Giuliani, as well as the 2001 terror attacks. Since 2004, he has been based in the Washington bureau of "The New York Times", where he is an investigative reporter who now writes about the Trump administration, as well as lobbying and corporate agendas in Congress. His previous assignments included the Department of Homeland Security and the Transportation Security Administration, as well as the aftermath of Hurricane Katrina.