(Jeffrey MacMillan/For the Washington Post)

This is a guest post by political scientists Tim LaPira and Herschel Thomas III.

In her appearance on “The Daily Show” with Jon Stewart last week, House Minority Leader Nancy Pelosi claimed that “the revolving door is not so much Congress as the executive branch.” The day after the episode aired, the Sunlight Foundation pointed out that 28 Pelosi staffers have spun through the revolving door to become lobbyists (or, at least, 28 staffers who registered as lobbyists).

And, her supposition appears to be in stark contrast to a Sunday front-page New York Times article showing that 1,650 aides have registered as lobbyists since 2007, when then-Speaker Pelosi led the passage of the Honest Leadership and Open Government Act.  According to Pelosi, that law was supposed to end “the tight-knit relationship between lobbyists and lawmakers.”

As political conjecture goes, this one is probably relatively minor.  She is certainly not the first politician to be taken off guard by Jon Stewart.  So, we give her the benefit of the doubt, and assume she was merely posing “the revolving door is not so much Congress as the executive branch” as a hypothesis.  Fortunately, we have data to put Pelosi’s revolving door hypothesis to the test.

In new article, “Revolving Door Lobbyists and Interest Representation,” we categorize previous employment for 1,600 randomly selected registered lobbyists.  Among them, 834 lobbyists had previously worked in the federal government, for a total of 1,495 government jobs, ranging from Cabinet secretaries and members of Congress down to congressional staff assistants.

So, what about Pelosi’s hypothesis?  Are revolving door lobbyists more likely to come from the federal bureaucracy and the White House, or from Capitol Hill?  About 65 percent of our “lobbyist-job” observations were in Congress, vs. only 23 percent in the bureaucracy, and 9 percent in the White House. (Note: some people may have worked in more than one position in Congress, so we count the “lobbyist-job,” not the lobbyist.)

When we account for people who held jobs in multiple branches of government, we find that congressional experience is by far the most common among lobbyists. More than three-fourths of the sample have worked in Congress.  And, when we break these categories down by party — whether a lobbyist’s former employer was a Democrat or Republican — we find no clear partisan bias among revolving door lobbyists across categories.  Lobbyists comes from both parties at an equal rate.

So, our data show the exact opposite pattern hypothesized by Pelosi.

Does that mean Jon Stewart is right when he asks “Is it possible that the people within the system don’t have enough distance from it to see that people in congressional offices end up going and becoming lobbyists in corporations, these corporations lobby to get all kinds of arcane things put in to the regulation?  Can our Congress, maybe, not see the corruption inherent in that?”  Not exactly.

At least, nothing in our analysis suggests that this practice is unethical, corrupt, or even illegal.  Most lobbyists are no Jack Abramoff.  They are very ethical, hard working, and honest and open about their work.   Lobbying is not some underhanded exchange of money for policy.  It’s the provision of sound, legislatively useful information to political allies.  Who could be better than congressional office “alumni” to provide that information?

But our article does suggest that former Hill staffers are more likely to work as hired-gun contract lobbyists, more likely to seek earmarks or other “arcane things,” and more likely to represent a wide variety of clients.  We interpret this to mean that they are probably not technocratic policy wonks who simply cut their teeth on Capitol Hill, but rather well-connected players who sell their access at a premium.  So, the revolving door doesn’t need to be inherently corrupt to raise concerns about its effect on political representation.