By Chris Adams

Capitol Hill is filled with lawmakers intent on passing a favored piece of legislation – or perhaps killing one favored by the opposition. Understanding what motivates them to do so is one of the most important roles of a congressional reporter.

But too often, understanding the why gets lost amid the frenetic day-to-day bustle in Congress.

In a session with Paul Miller fellows from the National Press Foundation, James Grimaldi offered a wealth of tips for investigating the underbelly of Congress – and gave reporters a strong reminder of the need to do so.

“Reporters aren’t doing it as often as I’d like to see them do it,” said Grimaldi (Twitter, bio), an investigative reporter for The Wall Street Journal who won a Pulitzer Prize for reporting on a major congressional lobbying scandal. He also won NPF’s Everett McKinley Dirksen Award For Distinguished Reporting of Congress for uncovering another congressional scandal.

Grimaldi explained the “iron triangles” of interest groups, executive branch agencies and public interest groups that dictate much of what gets done in Congress.

Then he detailed how reporters can work to understand – and, in some cases, expose corruption in – that iron triangle.

Among the dots reporters need to connect: the money that flows into candidates and their campaigns and related fundraising committees; lawmakers’ personal holdings, which are discoverable in disclosure reports filed at both state and federal levels; legislation that could help lawmakers’ financial backers, or even line lawmakers’ own pockets; constituent services that push the executive branch to take action on behalf of lawmakers’ friends or backers.

Such investigative work can yield a range of stories, from the unseemly to the corrupt. The “spectrum of stories” Grimaldi laid out included everything from basic background profiles to tales of bribery.