Roseville, CA…The central constitutional mechanism safeguarding our liberty is the separation of powers. It is Mother’s Rule writ large. Mother has one slice of pie and two hungry sons. How does she cut the pie so that both brothers are satisfied? One slices, and the other chooses. The ambitions of one perfectly counter the ambitions of the other. One cannot abuse his powers precisely because of the powers accorded the other.

Thus with our Constitution. One brother makes law but cannot enforce it; the other enforces law but cannot make it. One brother declares war but cannot wage it; the other wages war but cannot declare it. One brother appropriates money but cannot spend it; the other spends money but cannot appropriate it.

The Founders declared this principle to be a vital safeguard against tyranny and corruption, and rightly so. Imagine how differently Mother’s Rule would work if the same brother who sliced the pie also chose his piece.

Congress is now considering a return to earmarks – the practice of choosing the piece it has just sliced — or more precisely, of spending the money it has just appropriated.

This monumentally bad idea rests on two arguments. The first is that elected Members of Congress, and not unelected bureaucrats, should spend the people’s money. The problem, of course, is that representatives aren’t elected by all the people – only their own distinct constituencies. Congress gives collective voice to those constituencies as their representatives decide on the law and the appropriations to support it. But only the executive answers to the entire nation and can resist the manifest excesses of a body controlled by 535 demanding constituencies.

The second argument is that earmarks can “grease” legislation by buying off the votes of individual members whose judgment would otherwise oppose a measure. Add a few local projects of importance to that member, and suddenly a bill he would never vote for on its merits becomes a local imperative overriding his sound judgment. And if earmarks are to be handed out as a reward for voting for legislation, every congressman will prudently keep a list of earmarks required for his vote, whether or not he already plans to vote for the underlying bill.

Congress’ dysfunction isn’t for lack of earmarks. The House has just concluded one of its most prolific legislative years. The Senate has collapsed into dysfunction not because of the earmark ban, but because of the Republicans’ failure to reform the cloture rule.

This is not a theoretical discussion. We have learned the hard way what comes from breaching the Constitution’s checks and balances.

The first problem is the corrupting nature of earmarks. When we place the power to appropriate and the power to spend in the same hands, we bypass the most important check against corruption. A local company produces a product the Pentagon neither needs nor wants. What to do? Ingratiate yourself with the local congressman and – for the good of all those jobs in the district – have him tell the Pentagon what it needs and who will provide it. It should come as no surprise that most of the congressional corruption scandals of the 1990’s and 2000’s arose from abuses of earmarks.

Second, earmarks bypass the normal process where projects are considered competitively based on merit. Worthy projects do not need earmarks if appropriations are spent by the executive according to well established open-bid procedures. Earmarks are only required to protect unworthy projects from merit-driven competition. And even if there is such a thing as a “good” earmark, the price invariably is log-rolling all the bad ones.

Third, earmarks harm the central tenet of federalism: that local projects should be financed by local governments, and national expenditures should be reserved for the nation’s general welfare. A congressman who requests an earmark for his district ends up voting for thousands of other earmarks in other districts. All of them are for local projects that local officials obviously haven’t given high enough priority to fund from their own coffers. The result is a grab bag of dubious projects that rob St. Petersburg to pay St. Paul.

We’ve heard this Siren’s song before, and it didn’t end well.