There are many reasons to be concerned about both the impact of money on our political process and the Supreme Court's decision in Citizens United. But critics of Citizens United, including those calling for a constitutional amendment to overrule it, have too often made the mistake of grounding their argument on the claim that "money is not speech."

Organizations like Move to Amend, ballot measures in Boulder, Colorado and Madison Wisconsin, city council resolutions in Los Angeles and Portland, Oregon, and thousands of individuals protesting at the Supreme Court on the second anniversary of Citizens United have all embraced this slogan. Although the critics of Citizens United might well be right to condemn it and to call for a constitutional amendment to overrule it, they are misguided in their reliance on the refrain that "money is not speech."

Of course, money is not "speech." Money is money, a car is a car, and a ribbon is a ribbon. These are objects, not speech. But all of these objects, and many more besides, can be used to facilitate free speech. Consider a car. The government can lawfully impose all sorts of restrictions on how, when and where we can drive a car, and no one would argue that those restrictions implicate the First Amendment.

But suppose a city enacts a law prohibiting any person to drive a car in order to get to a political demonstration. Such a law would clearly implicate the First Amendment, not because a car is speech, but because the law restricts the use of a car for speech purposes.

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