In the early 1990s I attended a conference designed to teach journalists the tools of an emerging field known as computer-assisted investigative reporting. One of the hottest sessions of the conference explained how journalists could replicate stories that other papers had done locally using computer tools, including one especially popular project to determine if banks in your community were discriminating against minority borrowers in making mortgages. One newspaper, the Atlanta Journal-Constitution, had already won a Pulitzer Prize for its computer-assisted series on the subject, and others, including the Washington Post and the Detroit Free Press, had also weighed in with...