In a 5-4 decision, the Supreme Court eliminated an overall cap on how much an individual can give to campaigns. The opinion won't change  $2,600 cap on how much one donor can give to a specific candidate. Instead, the decision pertains to a set of two-year caps on individual donations overall to candidates and PACs of their choosing. Justices Alito, Scalia, and Kennedy joined Chief Justice Roberts's opinion in favor of striking down the limits, and Justice Thomas wrote a separate, concurring opinion. 

Republican donor Shaun McCutcheon challenged the Federal Election Commission's overall campaign limits on First Amendment grounds, as NBC News notes. Explaining his case, McCutcheon said, "It's about freedom of speech and your right to spend your money on as many candidates as you choose."

The justices, finding in favor of McCutcheon, agreed that the limits violated the First Amendment. The government defended the aggregate limits by arguing that they, like the individual limits, were there to prevent one individual from financially influencing any candidacy too much. Roberts disagreed, instead arguing that the limits "do little, if anything, to address that concern, while seriously restricting participation in the democratic process." Roberts, addressing the government argument that the regulations were intended to prevent corruption, added: 

Spending large sums of money in connection with elections, but not in connection with an effort to control the exercise of an officeholder's official duties, does not give rise to such quid pro quo corruption. Nor does the possibility that an individual who spends large sums may garner "influence over or access to" elected officials or parties...And because the Government's interest in preventing the appearance of corruption is equally confined to the appearance of quid pro quo corruption, the Government may not seek to limit the appearance of mere influence or access. See Citizens United, 558 U.S., at 360. 

As National Journal's Alex Steiz-Wald spotted, Roberts also cites unlimited independent expenditures in his decision against the aggregate limits. 

Under the aggregate limits, donors were restricted from giving more than $48,600 
to federal candidates and $74,600 to party committees and PACs in any two-year cycle. McCutcheon, according to a brief cited in the opinion, wanted to give tens of thousands of dollars over that limit to candidates and national Republican committees in the 2011-2012 cycle. Those limits prevented him from making additional donations. 

The case is McCutcheon v. Federal Election Commission. The full decision is below: 

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