Can you get convicted in a court of law based on your brain activity?

Are brain scan lie detectors going to be accepted?

And when does measuring somebody's brain count as illegal search and seizure? When does it violate the privacy of the mind?

What constitutional issues are triggered by all this? And what does this have to do with whether

your mouth gets dry when you lie? Or the orbits under your eyes get hot, or your voice constricts, and what the

networks in your brain are up to when you deceive.

Welcome to Inner Cosmos with me, David Eagleman.

I'm a neuroscientist and author at Stanford. And in these episodes, we sail

deeply into our three-pound universe to understand why and how our lives look the way they do.

Today's episode is about the fascinating topic of whether we can use technology to figure out whether a person is lying.

What is lie detection actually measuring? How good is it? When is it accepted in courts of law?

And as we come to have better and better brain reading technology, what is the future of lie detection?

So in a court of law, someone says, I didn't do it. I wasn't even there that night. I was in my apartment watching TV. If there's no

other information that can be gathered, like his cell phone was off, so there's no GPS signal,

and there's no eyewitnesses, there's no alibis, if there's no other information besides his

testimony, how do you know if that's really what happened or not?

Is he telling the truth or is he lying?

Now, on every crime television show, there are lots of clever clues that are surfaced by the

industrious detective, but the issue in real courts of law most of the time is that other

data just isn't available. So you only have the testimony of the people who were involved.

Most crime doesn't happen in fancy office buildings with full video coverage, but instead,

it more commonly happens in areas

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