We call it a war, and for 41 years we have been fighting it, a war on drugs.

The estimated cost so far, about $2.5 trillion, the results so far, mixed.

So what does it say that voters in Colorado and Washington State recently went to the ballot

box and decided to legalize one of the drugs we've been fighting all of these years, weed,

pot, marijuana.

What is that? Is it treason or is it a facing up to a certain social reality?

Those are a lot of questions, but they all boil down to the one that we're going to be debating

here tonight.

And here it is.

Yes or no to this statement, legalize drugs.

That is the motion on the table.

From Intelligent Squared U.S., I'm John Donovan.

We have four superbly qualified debaters who will be arguing four and against it, legalize

drugs.

We go in three rounds, then the audience votes to choose the winner and only one side wins.

Meeting our debaters, on the side arguing for the motion, legalize drugs.

Paul Butler, professor of law at Georgetown and former federal prosecutor.

After Harvard Law, you clerked for a judge, you worked in corporate law, you then became

a federal prosecutor and worked with the Department of Justice.

But then something happened that made you give it all up.

And it changed the way you thought about the criminal justice system.

What was it?

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