AUDIE CORNISH, HOST:
Let's turn now to another aspect of the special counsel's investigation - the extent of Russia's interference in the 2016 election. President Trump has repeatedly denied any involvement with Russia, but both the president and his personal attorney, Rudy Giuliani, are now arguing that collusion between the Trump campaign and Russia wouldn't actually be illegal had it happened.
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RUDY GIULIANI: I've been sitting here looking in the federal code trying to find collusion as a crime.
UNIDENTIFIED BROADCASTER: It's not.
GIULIANI: Collusion is not a crime. Everything that's been released so far shows the president to be absolutely innocent. He didn't do anything wrong.
CORNISH: That was Giuliani speaking yesterday on "Fox & Friends." He made a similar argument on CNN about the president's relationship with his former campaign chairman Paul Manafort.
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GIULIANI: He was never involved in intimate business relationships with Donald Trump. I mean, that just - four months - they're not going to be colluding about Russians (laughter), which I'm not even - know if that's a crime, colluding about Russians.
CORNISH: This morning, the president echoed Giuliani on Twitter saying, quote, "collusion is not a crime, but that doesn't matter because there was no collusion" - parentheses here - "except by crooked Hillary and the Democrats." That's the president's tweet. To help us understand what the law actually says or does not say about collusion is Paul Butler. He's a former prosecutor with the Department of Justice. He focused on white-collar crime, and he joins us now. Welcome.
PAUL BUTLER: Hey, Audie. It's great to be here.
CORNISH: So both Giuliani and Trump - we see they're making the argument that collusion isn't illegal, that it's not in the criminal code. Tell us what you know. What's the fact here?
BUTLER: If you look at the very long federal criminal code, which contains over 4,000 crimes, you won't find a crime called collusion. But you will find crimes that punish people for hacking into email or computers or election fraud or violating campaign financing laws. And then other laws punish people for conspiracy, which means working with other people to commit crimes. So at the end of the day, it's really just kind of a rhetorical device to say that collusion isn't a crime because special counsel Mueller certainly understands that. And so what he's charged most frequently is conspiracy to defraud the United States.
CORNISH: I also want to hear your thoughts on something else Rudy Giuliani said. On CNN yesterday, he floated this idea - that it wouldn't be illegal to receive hacked information from the Russians. Here it is.
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GIULIANI: If you got the hacked information from the Russians here at CNN and you played it, would you be in jeopardy of going to jail? Of course not.
CORNISH: All right. So here he is making the argument that, look; reporters might get hacked information, and they use it. They're not worried about prison time. Are there, Paul Butler, different rules for a presidential campaign?
BUTLER: There are not different rules, but the issue is criminal intent. And so if a campaign operative solicits or pays money for hacked email or if he or she knows that they're coming and deploys them in politically strategic ways - that is, they're welcoming this information because they want to use it to help elect a candidate - again, that goes to their mens rea, which is a fancy legal word for their knowing that they're doing something wrong.
CORNISH: Then there's this idea that campaigns are barred from accepting a thing of value from a foreign government. Could something like an email be considered a thing of value?
BUTLER: (Laughter) That's something that a judge would have to decide. So typically a thing of value - a campaign contribution is cash money. So the idea is if it's something different - for example, opposition research or dirt on Hillary Clinton - does that count as a thing of value? I think a judge could go either way.
CORNISH: What questions are you going to have going forward?
BUTLER: There's rarely a smoking gun in cases like this. And so as a prosecutor, what you do is look at documents and email and bank records. Sometimes, if you have cooperative witnesses, you have more of an insight into what the person's intent was. But these are often difficult cases to make. The Department of Justice there to just - they don't bring a case unless they think they can get a jury to convict. And so it takes a lot as a prosecutor to actually bring one of those cases.
CORNISH: That's Paul Butler. He served in the Justice Department under George H.W. Bush and Bill Clinton. He's now a professor at Georgetown Law. Thank you so much for speaking with us.
BUTLER: Great to be here.
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