American democracy functions in large part because the First Amendment protects the political speech rights of citizens and candidates from government interference.

American democracy functions in large part because the First Amendment protects the political speech rights of citizens and candidates from government interference.

Incumbent members of Congress, though, have sometimes overstepped First Amendment bounds by enacting campaign finance laws that limit citizens' ability to criticize them and protect them against electoral challenge.

The most egregious recent example of Congress members acting in their own self-interest at the expense of First Amendment rights was the McCain-Feingold campaign finance act of 2002.

McCain-Feingold barred certain grass-roots organizations from running advertisements even mentioning the name of a candidate for federal office within 60 days of an election. Last summer, the Supreme Court thankfully overturned large portions of this ban and eased restrictions on speech by citizens' groups.

The Supreme Court a few days ago heard a case concerning another incumbent protective element of McCain-Feingold. The case, Davis v. Federal Election Commission, challenges the so-called "Millionaires' Amendment" provisions in the law.

The Millionaires' Amendment raises the amount that an individual can contribute to a political campaign by at least 300 percent for a candidate facing a self-financed opponent.

On the surface, raising contribution limits is a welcome idea. Contribution limits restrict candidates' ability to raise money and, consequently, impact their ability to communicate with the voters. So increasing the amount of money individuals may contribute to campaigns will in turn increase the ability of candidates to disseminate their message.

Unfortunately, as is often the case when government starts tinkering with First Amendment rights, the costs of upholding the Millionaires' Amendment outweigh the benefit. Upholding the Millionaires' Amendment would do grave harm to the First Amendment over the long term by expanding the government's ability to regulate political speech.

Currently, the primary justification for regulating political speech is to prevent corruption -- or the appearance of corruption -- in candidates and officeholders. The Millionaires' Amendment depends on an entirely new justification for speech regulation -- that government can "level the playing field."

Such an egalitarian justification would give Congress a new quiver with which it can pierce the First Amendment. Government would be able to play the role of sound engineer and adjust the relative volume of certain speakers up or down to achieve preferred outcomes.

For example, New York City Council recently passed a law restricting the ability of anyone who has business before the city - like a zoning issue - to contribute to political campaigns. The city council, though, made one notable exemption. The council excluded labor unions from its list of restricted speakers. New York's law is also under court challenge, but more laws like it could be put on the books if government is allowed to "level the playing field."

But Congress, when passing the Millionaires' Amendment, was concerned about a different kind of level playing field. Congressman Tom Reynolds, during debate over McCain-Feingold, said, "my colleagues should live in fear, all 435 of us, that a wealthy American decides to run."

While the Millionaires' Amendment applies equally to incumbents and challengers, often only the incumbent has a list of maxed-out donors whom they can ask for more money. If incumbents truly cared about political competition they would raise contributions for all candidates.

The Supreme Court should tell members of Congress that they cannot arbitrarily tinker with First Amendment rights to protect themselves or their interests.

Bradley A. Smith is chairman of the Center for Competitive Politics and a former chairman of the Federal Election Commission. Smith is a professor at Capital University Law School.

Bradley A. Smith