The Volokh Conspiracy‘s David Bernstein did not believe John McCain did an adequate job explaining his concern with earmarks during last Friday’s Presidential debate. Bernstein pick up the argument:

Let’s say Congressman X is an idealistic young Congressman. Some constituents in his rural district ask him to get federal funding for a new emergency room in a local hospital, because the nearest emergency room is 100 miles away. Congressman X is skeptical of earmarks, but this particular one both seems like a good idea and a way to help ensure his reelection–he won his first term with only 52% of the vote. He manages to slip the hospital funding into an appropriations bill.

Soon thereafter, Congressman X becomes aware of a new $5 billion initiative that is a complete and utter boondoggle, but will benefit the districts of several influential congressmen. He starts sending out press releases opposing the initiative, and threatens to a force a vote on an amendment removing the initiative from the bill to which it is attached.

The senior Congressmen who support the initiative schedule a meeting with Congressman X. Like mafia thugs, they tell the Congressman, “It would be a real shame if anything was to happen to your hospital funding–and any future funding for your district, for that matter.” The message is clear; if Congressman X wants any hope of bringing federal money into his district, he had better stop opposing wasteful spending supported by his colleagues. He drops his opposition to the $5 billion project, gets the hospital funding, is reelected easily, and never again shows any “spending hawk” tendencies. Soon, in fact, he is rather senior himself, and finds himself meeting with a junior Congressman, telling him “It would be a real shame if anything was to happen to your hospital funding–and any future funding for your district, for that matter.”

So, even though earmarks are a small percentage of the federal budget, they are a very important part of a broader system of corruption that leads to out-of-control federal spending.

Bernstein is dead on. Correlation does not always equal causation but check out this chart of OMB data on the correlation between the number of earmarks and total federal spending:
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