The Supreme Court delves into campaign finance again.

From Marketplace, I'm Nancy Marshall Genser in for David Bancaccio.

Happy 4th of July.

Changes in the interpretation of campaign finance law could be on the horizon.

The Supreme Court is revisiting the topic.

It's been 15 years since the High Court decided that corporations and unions can give unlimited amounts of money to candidates.

But political parties have to work within separate limits when it's money used in tandem by the party and the candidate.

David Brancaccio is here with more.

To understand this, the key word is coordination,

political party and candidate working hand in hand to coordinate where the money goes,

typically the big bucks thing, campaign advertising. I can spend all the money I like saying

vote for Jane Smith for president, and it's unlimited as long

as I don't coordinate with her. But if I coordinate with her and say, Ms. Smith, I'd like to run an ad

that highlights your vision on gun control. And she says, that's fantastic. Please do that. Then we've

coordinated. That's David Kolker, senior counsel fantastic, please do that. Then we've coordinated.

That's David Kolker, Senior Counsel, at the Campaign Legal Center.

Now, he worked on a previous case involving this coordination issue that also ended up in the Supreme Court.

In that one from 2001, the High Court decided to keep limits on coordinated political party spending in an effort to minimize the effect of donors buying political influence.

And then what the court has said is that because of the coordination,

the potential for corruption is as great as if I had just written her a check.

So when there's coordination, it's equivalent

to contributions, and therefore it can be subject to limit. But now the Supreme Court has agreed

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