Today's 5-4 decision left intact the cap of $2,600 per election that a contributor to give to any single candidate for federal office, but it invalidated the separate limit on how much can be contributed to all federal candidates put together — $48,600 — as well as the total that can be given to political parties and PACs.
"The government may no more restrict how many candidates or causes a donor may support than it may tell a newspaper how many candidates it may endorse," write Chief Justice John Roberts for the court's majority.
The court said Congress can restrict contributions only to limit the ability of a contributor to give money to a candidate in return for a political favor — quid pro quo corruption. But, it said, merely spending large sums of money to support many candidates does not give rise to that kind of corruption.
The court dismissed as "far too speculative" the concerns of the Obama administration, which defended the law by warning that large donors could seek to channel their money through a variety of sources in order to evade the limits on how much can be contributed to a single candidate.
The law was challenged by the Republican Party and an Alabama businessman, Shaun McCutcheon, who argued that the contribution ceilings were an unconstitutional restriction on his free expression.
"It's about freedom of speech and your right to spend your money on as many candidates as you choose. It's a basic freedom," McCutcheon said in bringing the challenge.
Justice Steven Breyer, writing for the court's four dissenters, warned that the ruling gives big money donors greater leverage to swamp the system, drowning out the views of smaller contributors.
"Where money calls the tune, those ideas, representing the voices of the people, will not be heard."
Under the aggregate limits struck down by the court, an individual could donate a maximum of $48,600 to all candidates for federal office plus another $74,600 to national political parties, state and local political parties, and political action committees — a grand contribution total of $123,200 per election.
The dissenters said the decision was doubly damaging, coming after the Supreme Court ruling four years ago, in a case called Citizens United, that permitted corporations and labor unions to spend their own money to support candidates.
"The court substitutes for the current two-year overall contribution ceiling of $123,000 the number infinity. If the court in Citizens United opened a door, today's decision may well open a floodgate," Breyer said.
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