Can you measure pedophilia in a brain scan? Can you measure a lie from somebody's blood pressure?

And how should a judge in court, who's not an expert in science, decide these things?

What does any of this have to do with President Ronald Reagan or antisocial

personality disorder or how the television show CSI has impacted courtrooms? Welcome to Inner Cosmos with me,

David Eagleman. I'm a neuroscientist and an author at Stanford, and I've

spent my career at the intersection of our brains and our lives. And today's episode is about

an aspect of the intersection between brains and the legal system. And it's a tricky one.

The question is, when new neuroscience techniques are allowed in courts?

When should they be allowed?

What bars need to be passed for a technology to be accepted?

So let's start on March 30th, 1981, when the president of the United States, Ronald Reagan,

has been delivering a speech, and afterwards he and his team are returning to his limousine,

and he gives a two big arm wave to the crowd and suddenly there are gunshots

ringing out and everyone's diving and president reagan is hit with a ricochet off his limousine

and press secretary james brady falls and secret service agent tim mccarthy McCarthy Falls and a DC police officer named

Thomas Delahonte is also wounded and the president arrives at the emergency room in critical

condition and almost dies. And for those of you who weren't alive in 1981 or for whom this

has receded in memory, just try to picture the horror

that this entailed. Now, you may remember that the gunman, John Hinkley, had a deep psychosis. He was

divorced from reality. And he believed that if he shot the president, he would win the love of the actress Jody Foster.

There's a lot to say about this case.

And in episodes 36 and 37, I talked about the insanity defense.

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