Previous posts have noted that officially-reported spending on lobbying is on the decline. But there's a catch, as the Center for Responsive Politics explains:
Many observers theorize that a lot of lobbying has simply gone underground and is being done by individuals who are able to avoid the federal threshold for disclosure. To test this theory, CRP looked at lobbyists who were active in 2011 but not in 2012 and determined where they worked as of early 2013. Our research found 1,732 lobbyists who “deactivated” in 2012. This drop is considerably smaller than the recent peak of deactivated lobbyists in 2008. That year, following the passage of HLOGA in 2007, more than 3,400 lobbyists stopped reporting activity. Many argue that this decline is actually just an artifact of the new law's implementation: these lobbyists were likely not active before 2007, but the new requirements made reporting more onerous and so they were therefore disinclined to register.
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In the first analysis of this kind, CRP finds that 46 percent of the active 2011 lobbyists who did not report any activity in 2012 are still working for the same employers for whom they lobbied in 2011 -- supporting the theory that many previously registered lobbyists are not meeting the technical requirement to report or have altered their activities just enough to escape filing. It's possible that some individuals are being less than candid about how much time they spend lobbying, which is difficult to judge from the outside, as it is hard to determine the degree to which an employee’s duties have changed. But the fact that a near majority of deactivated lobbyists are still with the same organizations suggests that many of the changes we see in the filings may be due to technicalities or minor tweaks in their responsibilities, with the result being decreased reporting.