He returned to the national staff in Washington and worked as a reporter for seven years, covering labor, the U.S. Senate, the 1980 presidential campaign and the first Ronald Reagan administration.
In 2007, he wrote a series of articles there based on interviews of lobbyist Gerald Cassidy on the topic of lobbying in the United States.
From late 2008 through 2009, Kaiser followed Rep. Barney Frank (D-MA) and Sen. Chris Dodd (D-CT) as they wrote and passed the Dodd–Frank Wall Street Reform and Consumer Protection Act.
Kaiser's 2013 book, Act of Congress: How America's Essential Institution Works, and How It Doesn't, was based on this unusual access.
He has been a commentator on NPR's All Things Considered, and has appeared often on Meet the Press, the Today show and other television programs.