The Supreme Court imposed new limits Monday on states trying to restrain the influence of money in politics, striking down a law that tied the amount of public funds a candidate receives to how much privately funded rivals spend.
The 5-4 ruling was the latest in a series of decisions by the court's conservative majority upending campaign finance laws. But the court did not attack the validity of using public funds for campaign financing, giving a glimmer of hope to advocates of restrictions on spending in political campaigns.
Instead, Chief Justice John Roberts' majority opinion dwelled on the so-called trigger mechanism in an Arizona law that provided differing levels of money to publicly funded candidates based on the spending by privately funded rivals and independent groups.
The law was passed after a public corruption scandal and was intended to reward candidates who forgo raising their own campaign cash, even in the face of heavy spending by opponents with private money. Those who challenged the Arizona law said it caused them to rein in spending to prevent their political opponents from getting a fresh infusion of state money.
The court said the trigger violates the First Amendment, but left in place the rest of Arizona's public financing system.
"Laws like Arizona's matching funds provision that inhibit robust and wide-open political debate without sufficient justification cannot stand," Roberts said.
At least four other states, Maine, New Mexico, North Carolina and Wisconsin, have similar "trigger" provisions that affect some political races, and could be vulnerable.
Senate Republican leader Mitch McConnell of Kentucky praised the decision. "The Supreme Court ruled that a state cannot use taxpayer funds to punish a successful political campaign," McConnell said.
William Maurer, an attorney with the Institute for Justice representing the challengers, said the court reaffirmed its opposition to campaign spending laws that seek to level the playing field.
But Justice Elena Kagan said in dissent that the law was a reasonable response to political scandal. Reading a dissent aloud for the first time since joining the court last year, Kagan said that by providing candidates with additional money, the law actually provided for more, not less, political speech.
Arizonans "passed a law designed to sever political candidates' dependence on large contributors," Kagan said. "It put into effect a public financing system that attracted large numbers of candidates at a sustainable cost to the state's taxpayers."
Justices Stephen Breyer, Ruth Bader Ginsburg and Sonia Sotomayor signed onto Kagan's dissent.
On the federal level, candidates willing to abide by various spending limits receive public campaign money financed by the $3 that individual Americans can opt to check off on their tax returns.
This case follows other recent rulings striking down campaign finance laws. Among those were last year's Citizens United decision that removed most limits on election spending by corporations and organized labor, and a 2008 decision that voided the federal "millionaire's amendment" to increase contribution limits for congressional candidates facing wealthy opponents.
Roberts said the outcome in the Arizona case largely followed from the decision voiding the "millionaire's amendment."
A federal judge in Arizona also cited the Supreme Court decision in ruling against the Arizona Clean Elections program, but the U.S. 9th Circuit Court of Appeals in San Francisco found that the matching funds did not violate the First Amendment.
The chief justice _ joined by Justices Samuel Alito, Anthony Kennedy, Antonin Scalia and Clarence Thomas _ said nothing in the court's decision should be read as an attack on public financing generally.
Groups in favor of laws like Arizona's criticized the outcome, but took some solace from Roberts' rhetoric on public financing.
"After the court's ruling today, one key fact is clear. Public financing remains constitutionally strong," said Michael Waldman, executive director of New York University's Brennan Center for Justice. The center represented Arizona's Clean Elections Institute at the high court.
Trevor Potter, former chairman of the Federal Election Commission and adviser to Sen. John McCain's presidential campaigns, said the trigger allowed Arizona to dole out money only if private money pumped into a race exceeded certain thresholds.
"At a time when every state and locality is facing budgetary pressures, the trigger was a more parsimonious approach," Potter said.
Waldman said the decision would not threaten other types of public financing, including New York City's system of giving candidates extra money for bringing in small donations.
But Richard Hasen, an election law expert at the University of California at Irvine law school, said the New York program could be in legal jeopardy if the impetus for it was a desire to level the playing field, which the court has said is an impermissible basis.
The case is Arizona Free Enterprise Club v. Bennett, 10-238.
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