Bill Keller, former executive editor and columnist at The New York Times, is leaving the paper to join a nonprofit focused on the U.S. criminal justice system

Bill Keller, New York Times columnist since 2011, has decided to leave the publication in order to take on the role of editor-in-chief at a nonprofit startup, The Marshall Project, which is focused on the U.S. criminal justice system.

"It's a chance to build something from scratch, which I've never done before," Mr. Keller told The Times, "and to use all the tools that digital technology offers journalists in terms of ways to investigate and to present on a subject that really matters personally."

Before working as a columnist he was the executive editor of The Times from 2003-2011. Before that he was the Moscow and Johannesburg bureau chief, foreign editor and managing editor. Keller was awarded the Pulitzer Prize for his reporting on the dissolution of the Soviet Union in 1988.

The news of his departure was surprising for the editor of The Times' editorial page, Andrew Rosenthal. "But what an amazing opportunity," Rosenthal said. "If you want to do something new, this is a great area. My first thought, and this is purely self-centered, is that having another source of information on criminal justice is a great thing."

Keller, 65, will work alongside its founder Neil Barsky, a journalist turned Wall Street money manager. Keller will make the transition in early March. The website plans to raise money from foundations and individual donors, much like ProPublica's model.

"I don't think anybody finds it easy to leave The Times," said Keller. He added that The Times, "gave me a front-row seat at the end of the Soviet Union, and the end of white rule in South Africa, and then let me guide the newsroom through the transition to the web."