0:00:05 > 0:00:07What makes us good...
0:00:07 > 0:00:08or evil?
0:00:10 > 0:00:16Scientists are daring to investigate this unsettling question.
0:00:21 > 0:00:25They're trying to peel back the mask of the psychopathic killer.
0:00:29 > 0:00:33I hate to use the term evil, but there is something pretty scary about them.
0:00:33 > 0:00:35These are people without a conscience.
0:00:36 > 0:00:40What separates us from these terrifying people?
0:00:41 > 0:00:45Psychopaths really aren't the kind of person you think they are.
0:00:45 > 0:00:49They're exposing the biology that divides vice from virtue.
0:00:50 > 0:00:56If there's a chemical involved, we can not only measure it but we can manipulate it.
0:00:56 > 0:01:01What they're finding reveals something about the good and evil in us all.
0:01:01 > 0:01:04Bingo. When we broke the code, there it was.
0:01:04 > 0:01:06That group were the killers.
0:01:06 > 0:01:10Who, or what, is evil?
0:01:11 > 0:01:14I killed Leslie Bradshaw.
0:01:14 > 0:01:17Now, scientists are rewriting our ideas of right and wrong,
0:01:17 > 0:01:19even of crime and punishment.
0:01:19 > 0:01:24This is what one might call novel science, in that it is a new kind of science.
0:01:24 > 0:01:28I think this did affect whether he would live or die.
0:01:28 > 0:01:33What they're finding could turn your world upside down.
0:01:42 > 0:01:47In London, a group of researchers have devised a rather unusual experiment.
0:01:50 > 0:01:53They wanted to see, if we have a moral instinct,
0:01:53 > 0:01:56what might it look like in action?
0:01:58 > 0:02:02They've invited volunteers to face a stark moral choice.
0:02:02 > 0:02:05But they've added a twist.
0:02:05 > 0:02:09They're not going to rely on what their volunteers say they would do,
0:02:09 > 0:02:11but what they actually do.
0:02:13 > 0:02:16They've created an alternative world.
0:02:19 > 0:02:24No-one really knows themselves that well to know how they would respond in an extreme situation.
0:02:24 > 0:02:29Now, we wouldn't want to manufacture extreme situations in physical reality.
0:02:29 > 0:02:31But in virtual reality, you can.
0:02:34 > 0:02:38Everybody knows what they do has no real consequences.
0:02:38 > 0:02:43But nevertheless, there's a basic part of the brain that doesn't know virtual reality.
0:02:43 > 0:02:49It just makes people respond like they would in reality, at maybe a lesser level of intensity.
0:02:50 > 0:02:54The volunteers find themselves in an art gallery.
0:02:54 > 0:02:59Their role is to operate the lift and take visitors to the first floor.
0:03:02 > 0:03:06Five people are on the first floor and one on the ground floor.
0:03:08 > 0:03:12A man comes in and asks to be taken to the first floor.
0:03:15 > 0:03:18GUNSHOTS AND SCREAMING
0:03:22 > 0:03:26The man has started shooting the five people upstairs.
0:03:26 > 0:03:32Do they move him down, risking the life of one person on the ground floor in the hope of saving the five?
0:03:32 > 0:03:36Or do they do nothing?
0:03:36 > 0:03:40If they move the gunman down, they will be responsible for the death of that one person.
0:03:40 > 0:03:44If they leave him there, more people will die.
0:03:44 > 0:03:46But it won't be their fault.
0:03:47 > 0:03:50They actually have to do the action.
0:03:50 > 0:03:52They actually have to make the lift come down.
0:03:52 > 0:03:56It's like they're pressing a button to potentially kill one.
0:03:56 > 0:04:03One of the questions Mel is asking is how volunteers make this tough decision.
0:04:08 > 0:04:10GUNSHOTS AND SCREAMING
0:04:12 > 0:04:16I wasn't really thinking too much.
0:04:16 > 0:04:19I definitely acted with my emotions in there.
0:04:19 > 0:04:23Once he started shooting it was very much instinctive.
0:04:23 > 0:04:25I should get him out of the way of these people.
0:04:25 > 0:04:27GUNSHOTS AND SCREAMING
0:04:28 > 0:04:32I was stressed. I panicked.
0:04:32 > 0:04:38I was surprised and I couldn't manage to operate the buttons properly.
0:04:38 > 0:04:42Because I lost the plot! Basically.
0:04:46 > 0:04:50I was thinking, it's going to be a case of lots of people turn up at once, who do I put across?
0:04:55 > 0:04:58And then a gunshot happens.
0:04:58 > 0:04:59GUNSHOTS
0:05:05 > 0:05:11And all that logical thinking goes out of the window and you have to revert back to your instincts.
0:05:13 > 0:05:16I tried to move him down as quickly as possible, pressed the wrong button!
0:05:18 > 0:05:23Mel studied hundreds of people and has found a consistent pattern.
0:05:23 > 0:05:27I think it's a conflict between reason and emotion.
0:05:27 > 0:05:31There's an immediate reaction, an immediate need to do something.
0:05:31 > 0:05:36Then layered on top of this, a bit slower, is the cognitive response,
0:05:36 > 0:05:38the kind of rational, analytic response.
0:05:38 > 0:05:41But by that time it's already too late.
0:05:44 > 0:05:47Something had to change, something had to move.
0:05:47 > 0:05:51It just seemed better to get him downstairs, back where he came from.
0:05:51 > 0:05:55They may, post-hoc, be making a rationalisation.
0:05:55 > 0:05:57Yes, I wanted to save the majority.
0:05:57 > 0:06:00But my guess is that they just react out of instinct.
0:06:00 > 0:06:03I have to do something and do it fast.
0:06:03 > 0:06:05I didn't really think about the guy on the ground floor.
0:06:05 > 0:06:07I just thought, get him away from where there's lots of people.
0:06:07 > 0:06:10I don't think there was time to calculate or come up with anything clever.
0:06:10 > 0:06:13You just did what seemed the right thing to do.
0:06:13 > 0:06:16I couldn't control the lift as well as I would have hoped to have done.
0:06:16 > 0:06:18I forgot which was left and right.
0:06:18 > 0:06:19GUNSHOTS
0:06:19 > 0:06:24In the heat of the moment, they'd all instinctively tried to save the five.
0:06:24 > 0:06:29But once Emma had time to apply reason, she started to have doubts.
0:06:29 > 0:06:35I don't know... I'd like to tell myself I did that because in killing that one...
0:06:35 > 0:06:39If you yourself aided that, that's a bad thing and that would be on your conscience.
0:06:39 > 0:06:41It was confusing!
0:06:42 > 0:06:45No-one is right in these circumstances.
0:06:45 > 0:06:47If they choose to save the one, they're doing a moral act.
0:06:47 > 0:06:54If they choose to save the five, they're doing a moral act.
0:06:54 > 0:06:58Empirically, the majority do decide to try to save the five and sacrifice the one.
0:06:58 > 0:07:03I get the impression that people are moral beings and people really care about other people.
0:07:03 > 0:07:06And they try to do the best in the situation.
0:07:06 > 0:07:13And the remarkable thing is that they are driven, even though these are not actual human beings.
0:07:15 > 0:07:22It seems that when we are confronted with a difficult moral choice, we're confused, distressed.
0:07:22 > 0:07:25We may not know the right thing to do
0:07:25 > 0:07:29but we seem to have a moral impulse to try and do good.
0:07:31 > 0:07:34But just how embedded is this feeling?
0:07:34 > 0:07:36And where does it come from?
0:07:38 > 0:07:41What instincts, if any, are we born with?
0:07:49 > 0:07:54At Yale University, scientists have designed an ingenious experiment.
0:07:56 > 0:07:59They wanted to see if babies are born good or bad.
0:08:01 > 0:08:04Hundreds of parents have volunteered their children.
0:08:06 > 0:08:10The two scientists behind the project are Karen Wynne and Paul Bloom.
0:08:18 > 0:08:22I would give a year of my life to spend five minutes as a baby.
0:08:22 > 0:08:27To recapture what if feels like to be that sort of creature.
0:08:31 > 0:08:35I'm interested in the origin of morality, the origin of good and evil.
0:08:36 > 0:08:38We want to see what people start off with.
0:08:38 > 0:08:41Do they start of with a moral sense?
0:08:41 > 0:08:43With good impulses or evil impulses?
0:08:44 > 0:08:46And when you have a sense of that, you can ask,
0:08:46 > 0:08:53how does this develop into the adult sense of right and wrong, adult moral behaviour?
0:08:54 > 0:08:59They wanted to find out what is in a baby's brain.
0:08:59 > 0:09:05To try and unlock this secret, they've devised a kind of morality play that each baby will watch.
0:09:08 > 0:09:11So, this character has a ball that he is playing with.
0:09:11 > 0:09:15And he passes it to this other fellow,
0:09:15 > 0:09:19who returns it in a nice, reciprocal manner.
0:09:25 > 0:09:29But now, he's playing with his ball again.
0:09:31 > 0:09:34And he is now going to pass it to this other fellow,
0:09:34 > 0:09:36who takes it and runs away with it.
0:09:39 > 0:09:43What they're waiting to see is which character the baby will prefer.
0:09:45 > 0:09:47But how will they know?
0:09:49 > 0:09:55As an adult seeing this, the person who gave back the ball is good.
0:09:55 > 0:09:57The person who ran away with the ball is kind of a jerk.
0:09:59 > 0:10:02And for an adult, you just say, "Who's the good guy and who's the bad guy?"
0:10:02 > 0:10:03You can't do that with a young baby.
0:10:04 > 0:10:08So what you do is you hold them out and you get the baby to choose.
0:10:08 > 0:10:12The experimenter who hands the two puppets to the baby,
0:10:12 > 0:10:17she doesn't know which puppet was the good one and which puppet was the bad one.
0:10:17 > 0:10:20So she can't unconciously influence the baby's preference.
0:10:20 > 0:10:24Happy? Hi!
0:10:24 > 0:10:26Do you remember these guys from the show?
0:10:26 > 0:10:28Look at me. Which one do you like?
0:10:28 > 0:10:29CHILD GURGLES
0:10:32 > 0:10:34Which one do you like?
0:10:34 > 0:10:35CHILD CHATTERS
0:10:37 > 0:10:41- That one? Good job! - OK, that was the nice one.
0:10:42 > 0:10:44Aasrith had chosen the good puppet.
0:10:44 > 0:10:47The fact is, about 70% of babies do.
0:10:50 > 0:10:56Paul and Karen believe this is a sign that these babies are drawn towards kindness.
0:10:56 > 0:11:00And that this is a glimmer of a moral feeling.
0:11:04 > 0:11:07I was surprised that these experiments worked out as well as they did.
0:11:09 > 0:11:12These are very strong findings and we get them over and over again.
0:11:14 > 0:11:16That one? All right! Good job!
0:11:16 > 0:11:20I think we are tapping something that babies feel strongly about.
0:11:20 > 0:11:23These are not subtle effects.
0:11:23 > 0:11:29Rather, babies analyse these scenes in a rich and powerful way and respond accordingly.
0:11:31 > 0:11:36But if 70% choose the good guy, that leaves 30% who don't.
0:11:38 > 0:11:41So what does that say about those babies?
0:11:41 > 0:11:43We have always wondered about that.
0:11:43 > 0:11:46What do you do about the babies who reach for the bad guy?
0:11:46 > 0:11:49The sort of sexy explanation is these are psychopath babies,
0:11:49 > 0:11:51babies who see the world differently.
0:11:51 > 0:11:54Who actually prefer the bad guy.
0:11:55 > 0:11:58And I think that's a logical possibility.
0:11:58 > 0:12:01I think it's more likely that in any experiment you run,
0:12:01 > 0:12:06if you test 100 babies, 20 of them are going to act funny, no matter what.
0:12:06 > 0:12:09Because they just fall asleep or they get distracted.
0:12:10 > 0:12:14It's an open question whether babies who reach for the bad guy
0:12:14 > 0:12:19are different kinds of babies with a different moral code.
0:12:19 > 0:12:23As opposed to, it's just noise, it's the sort of noise you get in every experiment.
0:12:25 > 0:12:29The high percentage of babies who do pick the good puppet is striking.
0:12:31 > 0:12:37These are the first experiments to show that a moral instinct really seems present in babies.
0:12:38 > 0:12:45I'd suggest the moral sense we have as adults is already present by the time we reach our first birthday.
0:12:49 > 0:12:53Most of us seem to start life with good impulses, not bad.
0:12:54 > 0:13:00The inclination to help each other, to empathise, seems to be built into our brains.
0:13:01 > 0:13:05We feel distress when we see someone in pain.
0:13:05 > 0:13:06But why?
0:13:08 > 0:13:14The fact that this is such a strong feeling has inspired a new and bold scientific quest.
0:13:26 > 0:13:29Human beings are obsessed with morality.
0:13:29 > 0:13:33We need to know why people are doing what they're doing.
0:13:33 > 0:13:36And I, indeed, am as obsessed with morality.
0:13:36 > 0:13:40I really want to know when people are good and evil, and why that occurs.
0:13:40 > 0:13:43Paul Zak is a neuroscientist.
0:13:45 > 0:13:49His mission is to try and trace the basis of our morality.
0:13:49 > 0:13:54So I was really looking for a chemical basis for these behaviours.
0:13:54 > 0:14:00If there is a chemical involved, that means we can not only measure it but we can manipulate it.
0:14:01 > 0:14:06Paul wanted to find the actual chemicals that drive our behaviour.
0:14:06 > 0:14:10And to do that, he's doing an experiment he's never done before.
0:14:13 > 0:14:19He's bringing his lab outside to see if he can catch good, co-operative behaviour.
0:14:25 > 0:14:29He's using a group of people who don't know each other well
0:14:29 > 0:14:33but are going to have to work together if they want to succeed.
0:14:39 > 0:14:44Hi, guys, thanks for coming out and burning part of your Saturday to be with us.
0:14:44 > 0:14:49So, we want to do this experiment where we want to find out how do you bond as a group?
0:14:49 > 0:14:50And that's intuitive.
0:14:50 > 0:14:52But we want to find some neuroscience behind this.
0:14:55 > 0:14:59Paul thinks their brain chemistry may undergo a transformation.
0:15:00 > 0:15:04They may release a chemical that will make them feel empathy.
0:15:05 > 0:15:10If this is true, this chemical could be driving our morality.
0:15:11 > 0:15:13It could be the moral molecule.
0:15:17 > 0:15:21We see lots of cooperation in the world but we don't know why.
0:15:21 > 0:15:26So I began wondering if there was an underlying biological basis for co-operation.
0:15:26 > 0:15:28If there was,
0:15:28 > 0:15:32could there be an underlying chemical foundation for this?
0:15:32 > 0:15:37One of the chemicals he's interested in he knows is active within families.
0:15:37 > 0:15:41But he has never looked for it in a team of relative strangers.
0:15:42 > 0:15:48This chemical, oxytocin, that motivates co-operation, is triggered in a variety of ways.
0:15:48 > 0:15:52It's released in little children when they are nurtured by their mothers when they are breast-fed.
0:15:52 > 0:15:54It's released during touch.
0:15:54 > 0:15:58We found it's even released when complete strangers trust us.
0:15:58 > 0:16:00So the next question we want to ask is,
0:16:00 > 0:16:04are there a variety of rituals that may induce oxytocin release
0:16:04 > 0:16:08and lead to bonding among groups, even among groups of strangers?
0:16:10 > 0:16:13One of these rituals could indeed be the pre-match warm-up.
0:16:15 > 0:16:17So we are going to take a baseline blood draw
0:16:17 > 0:16:20and find out what his baseline physiologic state is
0:16:20 > 0:16:23and then we'll measure after the warm-up how it changes.
0:16:23 > 0:16:27So each individual is different so it's important to get a baseline for each individual.
0:16:27 > 0:16:29OK.
0:16:50 > 0:16:53What they are really doing is training their movements together,
0:16:53 > 0:16:58getting in sync, so they are actually forming themselves as almost a super organism.
0:17:00 > 0:17:04Coming together, they're warming up their muscles.
0:17:04 > 0:17:07At the same time, they are warming up their brains.
0:17:07 > 0:17:10Their brains are starting to bond together.
0:17:10 > 0:17:13So as a group they can be aggressive against the other team.
0:17:16 > 0:17:19OK, we're starting the second blood draw in just a minute.
0:17:20 > 0:17:24At the end of the warm-up, Paul prepares for the second blood draw.
0:17:27 > 0:17:32As the blood is sent back to the lab, the match got underway.
0:17:34 > 0:17:38This is where we are seeing the real payoff from that warm-up.
0:17:38 > 0:17:40They're working as a group.
0:17:40 > 0:17:42Oh, look at him go! He almost made it.
0:17:45 > 0:17:48Two weeks later and Paul had the results.
0:17:48 > 0:17:49This is a brand-new experiment.
0:17:49 > 0:17:52We don't really know what we're going to find.
0:17:53 > 0:17:56The oxytocin levels of the players had, in fact, converged,
0:17:56 > 0:17:59getting them in sync with each other.
0:17:59 > 0:18:01This would have helped them feel bonded
0:18:01 > 0:18:06and confirms what Paul has found in his many laboratory experiments.
0:18:06 > 0:18:11Oxytocin seems to be the key to empathy.
0:18:11 > 0:18:13I call oxytocin the moral molecule.
0:18:15 > 0:18:20When oxytocin is released we feel empathy, we feel attachment, we connect to people.
0:18:21 > 0:18:24But the results showed something else.
0:18:24 > 0:18:28Another hormone, testosterone, had increased.
0:18:28 > 0:18:31And this drives aggressive behaviour.
0:18:31 > 0:18:36So is testosterone the opposite of the moral molecule?
0:18:38 > 0:18:43Oxytocin makes us more selfless and testosterone makes us more selfish.
0:18:43 > 0:18:47What's interesting in the ritual setting like with the rugby team
0:18:47 > 0:18:49is that sometimes these run together.
0:18:49 > 0:18:54So if the rugby players want to be both selfless, they want to support their team
0:18:54 > 0:18:58but also selfish, they want to grab goals from the other team.
0:18:58 > 0:19:01And that's pretty interesting, so they're not always in conflict.
0:19:01 > 0:19:09Paul believes that what happens on the sports field reflects our moral battlefield in life.
0:19:09 > 0:19:12The way to think about this is that rugby is like society in miniature.
0:19:12 > 0:19:15We have to co-operate as a group to achieve a goal.
0:19:15 > 0:19:18But yet we have another group that's trying to stop us from doing that.
0:19:18 > 0:19:21So there's a balance between testosterone and oxytocin.
0:19:21 > 0:19:23There's a way to understand how societies work.
0:19:28 > 0:19:36What we experience as a battle between good and evil may be a chemical battle waging inside us.
0:19:38 > 0:19:41Perhaps being moral means achieving a balance.
0:19:41 > 0:19:45For each one of us, that process will be different.
0:19:50 > 0:19:53But what happens if you try and disturb that balance?
0:19:53 > 0:19:58If you make someone more aggressive than they naturally are?
0:19:59 > 0:20:04What does it do to a human if you suppress their own moral instinct?
0:20:06 > 0:20:09MILITARY DRUMROLL
0:20:14 > 0:20:17Not all experiments are planned.
0:20:17 > 0:20:20Here in Quantico, Virginia,
0:20:20 > 0:20:23Marines are part of a radical training programme
0:20:23 > 0:20:27that has implications far beyond this camp.
0:20:31 > 0:20:35The two warriors at the centre of it are Captain Hoban
0:20:35 > 0:20:40and Lieutenant Colonel Shushko.
0:20:40 > 0:20:41HE YELLS
0:20:41 > 0:20:43'Marines know from day one
0:20:43 > 0:20:47'if they are given a mission. they have got to accomplish it.'
0:20:47 > 0:20:50That does mean they will have to take a life,
0:20:50 > 0:20:53so how do you train to take a life?
0:20:53 > 0:20:57You're going to grab your training knives, batons,
0:20:57 > 0:20:59and then set up on LZ6...
0:20:59 > 0:21:01'What the marines must do goes against
0:21:01 > 0:21:04'their natural moral instinct.'
0:21:05 > 0:21:08It's not in human nature to take somebody's life.
0:21:08 > 0:21:10I don't think it's easy to kill somebody.
0:21:10 > 0:21:13It's not easy to even think about killing somebody.
0:21:15 > 0:21:19Because it's so unnatural, the marines learn step by step.
0:21:19 > 0:21:23'When we start a marine out, we do have him crawl, before he walks.
0:21:23 > 0:21:24'before he runs.'
0:21:24 > 0:21:26To the head, to the head!
0:21:26 > 0:21:29'Learning the basics of standing, falling
0:21:29 > 0:21:32'throwing punches, throwing kicks, being thrown.'
0:21:32 > 0:21:35Then we add a simple thing like a knife.
0:21:35 > 0:21:38'How to hold a knife, how to use a knife with your good hand.
0:21:38 > 0:21:40'with your bad hand.'
0:21:40 > 0:21:42Switch hands with the knife, kill him!
0:21:42 > 0:21:46'How to use a baton. Same thing, how to use a pistol.'
0:21:46 > 0:21:48Then you practise it over and over again
0:21:48 > 0:21:52They start getting more confident, so it becomes second nature.
0:21:54 > 0:21:58From constantly training, it becomes muscle memory
0:21:58 > 0:21:59and your body naturally reacts.
0:22:03 > 0:22:05I'm a firm believer that if you practise something,
0:22:05 > 0:22:07after 21 days it becomes a habit.
0:22:07 > 0:22:12The act of repetition is aimed to push men over the natural barrier
0:22:12 > 0:22:17that holds them back from harming.
0:22:17 > 0:22:22A combat mindset is being able to turn the switch on when you have to.
0:22:22 > 0:22:25So that when the time comes
0:22:25 > 0:22:27and it's my life or yours
0:22:27 > 0:22:30or an innocent bystander's life, we know how to react.
0:22:30 > 0:22:33And we don't think twice about it.
0:22:33 > 0:22:37- So if that means killing someone, you're able to do it?- Yes.
0:22:41 > 0:22:46Equipping them with the ability to kill must be combined
0:22:46 > 0:22:48with the motivation to do so.
0:22:48 > 0:22:53In the past, that motivation was often hate.
0:22:56 > 0:22:59When I was trained, we were trained as killers.
0:22:59 > 0:23:00The easy way out.
0:23:00 > 0:23:04Fill in the blank with some pejorative of a subhuman,
0:23:04 > 0:23:07whether it's a gook in Vietnam
0:23:07 > 0:23:10or a hajj in the conflicts we are in now,
0:23:10 > 0:23:15"He did this, he's subhuman. Kill him like an animal."
0:23:15 > 0:23:19Well, it turns out that you can try to take that approach,
0:23:19 > 0:23:22but it comes back to haunt you.
0:23:26 > 0:23:30What they found was that ignoring the Marines'
0:23:30 > 0:23:34natural sense of morality was starting to destroy them.
0:23:37 > 0:23:40We had people abusing their families and their wives.
0:23:40 > 0:23:44they're knocked so far off that way, that now everybody is the enemy.
0:23:44 > 0:23:47they start to lose respect for all life,
0:23:47 > 0:23:50including former friends and family.
0:23:50 > 0:23:53Taking away all their ethical parameters
0:23:53 > 0:23:57was removing something fundamental to their brains.
0:23:57 > 0:24:00Human beings are not natural killers.
0:24:00 > 0:24:03When we have tried, over the centuries,
0:24:03 > 0:24:06to make soldiers more effective killers,
0:24:06 > 0:24:09we may have been effective in the short run.
0:24:09 > 0:24:12But when they get back afterwards
0:24:12 > 0:24:14and they think about what they've done,
0:24:14 > 0:24:18it's not psychologically healthy for them.
0:24:18 > 0:24:21They had to come up with a new plan that somehow worked
0:24:21 > 0:24:24with their moral instinct, not against it.
0:24:24 > 0:24:27What we did is we backed up and thought "What are people?"
0:24:28 > 0:24:31If they're not killers, what are they?
0:24:31 > 0:24:36If you think about it, people are naturally protectors.
0:24:36 > 0:24:39So if you work off that,
0:24:39 > 0:24:42would people protect and defend
0:24:42 > 0:24:45to the point of killing?
0:24:45 > 0:24:47Yes, they would. But only when necessary
0:24:47 > 0:24:49to protect and defend life.
0:24:51 > 0:24:55What we think is if we calibrate their moral compass,
0:24:55 > 0:24:58make them ethical warriors,
0:24:58 > 0:25:02whose mission is to protect and defend life,
0:25:02 > 0:25:05killing only when necessary to protect life.
0:25:08 > 0:25:12'So for the Marines, morality has had to become part
0:25:12 > 0:25:15'of their new narrative.
0:25:15 > 0:25:19'It seems our moral instinct cannot be suppressed
0:25:19 > 0:25:22'without paying a heavy price.'
0:25:22 > 0:25:25Don't fly too early. You don't want to get tracked.
0:25:28 > 0:25:32But if our natural instinct is to do no harm,
0:25:32 > 0:25:36how can we explain those who seem totally devoid of this feeling?
0:25:36 > 0:25:40Who have no revulsion at taking a life?
0:25:44 > 0:25:49Scientists have embarked on a new, dark voyage to understand evil.
0:25:49 > 0:25:54They've turned to the serial killer psychopath.
0:26:04 > 0:26:09One man has done more than anyone to understand the mind of a psychopath.
0:26:11 > 0:26:14Psychologist Professor Bob Hare
0:26:14 > 0:26:17set out on this trail 30 years ago.
0:26:17 > 0:26:22He was determined to penetrate what lay beneath the mask.
0:26:27 > 0:26:30I'm looking at two pictures of very well-known,
0:26:30 > 0:26:34infamous serial killers, Jeffrey Dahmer and Ted Bundy.
0:26:34 > 0:26:37When you look at the pictures, you see ordinary people.
0:26:37 > 0:26:40That was their strong point. They looked perfectly ordinary
0:26:40 > 0:26:43when they were out in society.
0:26:43 > 0:26:47After the fact, of course, we realise they were far from normal.
0:26:47 > 0:26:50They're very deviant, cold-blooded killers.
0:26:52 > 0:26:55This was a world he came into by accident.
0:26:56 > 0:26:57I needed a job,
0:26:57 > 0:27:01the only job I could find at the time was as the sole psychologist
0:27:01 > 0:27:03at the OBC Penitentiary,
0:27:03 > 0:27:06a maximum security institute near Vancouver.
0:27:06 > 0:27:10Bob found himself face to face with psychopaths.
0:27:10 > 0:27:13When I was first starting out, I had no idea at all
0:27:13 > 0:27:16about the sorts of people with whom I was dealing.
0:27:16 > 0:27:21They were people. Some would be very difficult to deal with.
0:27:21 > 0:27:25You could see there was something strange about them, even predatory.
0:27:25 > 0:27:29I hate to use the term evil, but something pretty scary about them.
0:27:29 > 0:27:33But many of them were open, warm-appearing people
0:27:33 > 0:27:36until you find out what they've done.
0:27:43 > 0:27:46'NEWS REPORT: Parts of 11 different bodies were found in Dahmer's flat
0:27:46 > 0:27:48'when he was arrested on Tuesday.'
0:27:48 > 0:27:52He wanted to find the rules of a psychopath.
0:27:52 > 0:27:56'I'm the same person I was on the street, except for the killing.
0:27:56 > 0:28:01'I'm still someone's brother, someone's son.'
0:28:01 > 0:28:04I tried to find out what makes them tick. What they have in common
0:28:04 > 0:28:07and why do they have these things in common.
0:28:07 > 0:28:10'I never once had any guilt.'
0:28:10 > 0:28:12Who are they?
0:28:12 > 0:28:16How do we go about assessing this guy, saying he's psychopathic?
0:28:16 > 0:28:18'I never once shed any tears.'
0:28:18 > 0:28:21We had to have some sort of diagnostic criteria.
0:28:21 > 0:28:23Bob drew up a checklist
0:28:23 > 0:28:27defining their core personality traits.
0:28:29 > 0:28:32The essential features of psychopathy
0:28:32 > 0:28:35would include a profound lack of empathy.
0:28:35 > 0:28:39I don't mean a general, I mean a profound lack of empathy.
0:28:39 > 0:28:42A general callousness towards other people.
0:28:42 > 0:28:45these are people without a conscience, shallow emotions.
0:28:45 > 0:28:49"I'm number one in the universe, there's nobody else."
0:28:54 > 0:28:58He then devised an experiment looking into their brains.
0:29:04 > 0:29:08A psychopathic killer who volunteered was Anthony Frazzel.
0:29:08 > 0:29:13If we assume, and the evidence supports this, that psychopaths
0:29:13 > 0:29:16have a severe blunted emotional life,
0:29:16 > 0:29:18the emotions aren't as powerful,
0:29:18 > 0:29:21they don't have the same range they have for most people,
0:29:21 > 0:29:24it should be reflected in things like their language.
0:29:27 > 0:29:30Bob showed Frazzel both real and made-up words
0:29:30 > 0:29:33and asked him to spot the difference.
0:29:33 > 0:29:37Some of those words would have an emotional charge.
0:29:37 > 0:29:41Most people can decide very quickly when it's emotional.
0:29:41 > 0:29:43More quickly than a neutral word. There's a difference.
0:29:43 > 0:29:47The brain responses to the emotional words are quite different
0:29:47 > 0:29:50than they are to neutral words.
0:29:50 > 0:29:53For psychopaths, there was absolutely no difference.
0:29:53 > 0:29:55A word was a word was a word.
0:29:55 > 0:30:02The word rape had the same emotional impact as the word table or tree.
0:30:02 > 0:30:06He ran the experiment with dozens of psychopaths
0:30:06 > 0:30:08and got the same result.
0:30:08 > 0:30:14They were so dramatic that reviewers simply didn't believe the findings came from real people.
0:30:14 > 0:30:18So we rewrote it, explained it in more detail
0:30:18 > 0:30:21and sent it into another top journal, Psychophysiology.
0:30:21 > 0:30:24It was published and it's actually a seminal study.
0:30:30 > 0:30:36Bob Hare identified one of the lines that might separate good from evil.
0:30:36 > 0:30:39It was our emotions.
0:30:39 > 0:30:43Psychopaths simply did not seem to have the feelings of empathy
0:30:43 > 0:30:45that stop the rest of us from harming.
0:30:46 > 0:30:49The search had begun.
0:30:49 > 0:30:55What else could we see if we peered into the brain of the psychopath?
0:31:08 > 0:31:16In California, neuroscientist Jim Fallon found himself almost by accident picking up the quest.
0:31:18 > 0:31:22He had specialised in standard clinical disorders.
0:31:23 > 0:31:28Now he was about to become an expert in the brains of psychopaths.
0:31:32 > 0:31:34I spent a lot of my research career
0:31:34 > 0:31:37looking at different brain abnormalities.
0:31:37 > 0:31:41Mostly schizophrenia but also depression and addictions of different sorts.
0:31:41 > 0:31:45And then my colleagues started to do something different.
0:31:46 > 0:31:51They asked him to analyse a variety of brain scans.
0:31:51 > 0:31:57What he didn't know was some of them were the brain scans of murderers.
0:31:57 > 0:31:58They brought me these scans and said,
0:31:58 > 0:32:01"What do you think of these? What do you see?"
0:32:06 > 0:32:08There were normals mixed in.
0:32:08 > 0:32:11People with schizophrenia, depression and there were killers.
0:32:11 > 0:32:14But I didn't know the mix. It was just like, "Here it is."
0:32:17 > 0:32:21About halfway through I noticed a pattern. It was fascinating.
0:32:21 > 0:32:24This one group, no matter what other damage they had or didn't have,
0:32:24 > 0:32:27they always had damage of the orbital cortex above the eyes.
0:32:31 > 0:32:34The other part of the brain that looked like wasn't working right
0:32:34 > 0:32:38was the front part of the temporal lobe which houses the amygdala.
0:32:38 > 0:32:41That is where your different animal drives are.
0:32:41 > 0:32:43I said, "This is extraordinary."
0:32:43 > 0:32:47So I separate out the piles and I said, "This is a different group."
0:32:48 > 0:32:52And bingo, when we broke the code, there it was.
0:32:52 > 0:32:53That group were the killers.
0:32:53 > 0:32:57It was really one of those "ah-hah" moments.
0:32:58 > 0:33:00The areas that looked abnormal
0:33:00 > 0:33:05were crucial for controlling impulsivity and emotions.
0:33:05 > 0:33:11Fallon's images seem to confirm what Hare's work had suggested.
0:33:11 > 0:33:17It looked like we were getting closer to the signature brain profile of the serial killer.
0:33:17 > 0:33:22This is about as dramatic as a difference can be in a PET scan.
0:33:22 > 0:33:25It's just a mind-blower, really.
0:33:26 > 0:33:29The location of these abnormalities
0:33:29 > 0:33:30indicated to Jim
0:33:30 > 0:33:34why psychopaths could be driven towards extreme behaviour.
0:33:37 > 0:33:42Just to get up to the point of being satisfied of feeding the amygdale,
0:33:42 > 0:33:46that whole system, some of these psychopaths do extraordinary things.
0:33:46 > 0:33:50Somebody like that may have to fly to Vegas and get drunk,
0:33:50 > 0:33:53and be with a bunch of prostitutes or snort cocaine,
0:33:53 > 0:33:56or kill somebody over and over again.
0:34:02 > 0:34:05It really indicated that there was a biological basis,
0:34:05 > 0:34:09a really hardcore brain basis, for this urge to kill.
0:34:11 > 0:34:13That brings the other question,
0:34:13 > 0:34:18is that enough to cause someone to be a psychopath or a killer?
0:34:18 > 0:34:21Or are there other factors?
0:34:21 > 0:34:26That moment was immediately followed by a bunch of question marks.
0:34:30 > 0:34:35Once it seemed that the brains of psychopaths were different,
0:34:35 > 0:34:38the next urgent question was why?
0:34:39 > 0:34:43Back in Vancouver, the direction seemed clear.
0:34:43 > 0:34:45The path to pursue was genes.
0:34:46 > 0:34:51Once we had determined there were certain differences in brain function and structure,
0:34:51 > 0:34:56the next question is, where do they originate from?
0:34:56 > 0:34:58That brings up questions of genetic factors.
0:35:00 > 0:35:05All behaviour, all physical features have strong genetic contributions.
0:35:07 > 0:35:10The search was on.
0:35:10 > 0:35:13Where there genes that linked to violence?
0:35:14 > 0:35:19In 1993, the breakthrough came with one family's history.
0:35:19 > 0:35:23Here all the men had a background of violence
0:35:23 > 0:35:25and all lacked the same gene.
0:35:28 > 0:35:30There was one gene that was missing
0:35:30 > 0:35:33and it was in the men and all these men were violent.
0:35:36 > 0:35:41What was important was that the loss of one gene profoundly affected behaviour.
0:35:41 > 0:35:46That kind of supported idea that one gene really controlled behaviour.
0:35:46 > 0:35:51It then emerged that just being born with one variant of this gene
0:35:51 > 0:35:54could also predispose you to violent behaviour.
0:35:54 > 0:36:00The MAO-A gene became known as the warrior gene.
0:36:00 > 0:36:03That was pretty exciting because it implied first off
0:36:03 > 0:36:09that we could identify specific contributing factors to psychopathy
0:36:09 > 0:36:13but also because it suggests that
0:36:13 > 0:36:17this particular area of research is bound to be fruitful.
0:36:21 > 0:36:26It seemed that it could be possible to trace the hallmark of evil
0:36:26 > 0:36:29in people's brains and genes.
0:36:29 > 0:36:33So did this mean that if you had both elements
0:36:33 > 0:36:36you were destined to become a killer?
0:36:36 > 0:36:40For Jim Fallon, this question was about to become deeply personal.
0:36:56 > 0:36:58At a regular family party,
0:36:58 > 0:37:02a casual remark by his mother took him by surprise.
0:37:04 > 0:37:09As we were discussing this, and different brains, I said to him,
0:37:09 > 0:37:14"You should look into your own history."
0:37:14 > 0:37:16I said, "Did you ever hear of Lizzie Borden?"
0:37:16 > 0:37:20and I started telling the story about Lizzie Borden
0:37:20 > 0:37:23and how she had murdered her father and mother.
0:37:23 > 0:37:26I said, "There's a cousin of yours."
0:37:28 > 0:37:30Well, he was shocked
0:37:30 > 0:37:33and, of course, started to delve a little further into this.
0:37:35 > 0:37:37It was pretty startling.
0:37:37 > 0:37:39I knew it was true. She doesn't make things up.
0:37:39 > 0:37:42There were quite a few murderers in that family.
0:37:45 > 0:37:50At least 16 murderers in the one line.
0:37:52 > 0:37:56Hearing this, Jim took the bold decision to run a check
0:37:56 > 0:37:59on the entire family for the genes and brain structure
0:37:59 > 0:38:03linked to violent psychopathic behaviour.
0:38:04 > 0:38:07The results of the brain scans came back first.
0:38:10 > 0:38:14There were many, many sheets and they all looked normal. Fantastic.
0:38:14 > 0:38:18And then I came to one and it was the last one, as it turns out,
0:38:18 > 0:38:21and it looked very abnormal.
0:38:21 > 0:38:28This particular PET scan had no orbital cortex activity.
0:38:28 > 0:38:30It had no temporal lobe activity.
0:38:30 > 0:38:33The whole limbic system was not functioning.
0:38:33 > 0:38:36I said, "Oh my god, it's one of these killers.
0:38:36 > 0:38:39"It's the exact same pattern as a killer."
0:38:39 > 0:38:43When I looked down at the code, it wasn't one of the killers. It was me.
0:38:45 > 0:38:50It was really a shock but I tried to think, "That's really interesting."
0:38:50 > 0:38:53"I'm not in jail, haven't killed anybody or done that stuff.
0:38:53 > 0:38:57"At least I don't have the genes. I just have the brain pattern."
0:38:57 > 0:39:00I said, "OK". I felt better.
0:39:00 > 0:39:04He then did the gene tests, looking not only for the warrior gene
0:39:04 > 0:39:07but for other traits, like impulsivity,
0:39:07 > 0:39:11that make up the profile of a psychopath.
0:39:11 > 0:39:13Back came the results.
0:39:13 > 0:39:16Again, everybody had a mix of things in our family.
0:39:16 > 0:39:21It looked like an average mix of these different genes
0:39:21 > 0:39:25that have to do with aggression and all sorts of behaviours,
0:39:25 > 0:39:29except now again there was one that showed all of these high risk genes.
0:39:29 > 0:39:30And it was mine.
0:39:32 > 0:39:34What are the odds of getting these?
0:39:34 > 0:39:38To throw the dice 20 times and it comes up six-six, six-six, six-six?
0:39:38 > 0:39:40It's millions to one.
0:39:41 > 0:39:46Now Jim started asking himself some unsettling questions.
0:39:47 > 0:39:53This really became probably more serious in my mind
0:39:53 > 0:39:56because it's like, who am I really?
0:39:56 > 0:39:59People with far less dangerous genetics
0:39:59 > 0:40:02become killers and are psychopaths than what I had.
0:40:02 > 0:40:04I had almost all of them.
0:40:06 > 0:40:10But the reaction from his family was to unsettle him even further.
0:40:12 > 0:40:14I knew there was always something off.
0:40:14 > 0:40:20It makes more sense now that, it's clear he does have the brain
0:40:20 > 0:40:23and genetics of a psychopath.
0:40:23 > 0:40:25It all falls into place, as it were.
0:40:27 > 0:40:29He's got a hot head.
0:40:29 > 0:40:36Everything you'd want in a serial killer, he has in a fundamental way.
0:40:36 > 0:40:39Because I've been scared of him a few times.
0:40:41 > 0:40:43Thanks.
0:40:43 > 0:40:45It was surprising but not surprising.
0:40:45 > 0:40:48Because he really is in a way, two different people.
0:40:48 > 0:40:52Even though he's always been very funny and gregarious,
0:40:52 > 0:40:55he's always had a stand-offish part to him.
0:40:55 > 0:40:58And that's always been there. That's always been there.
0:41:00 > 0:41:02We'll drink to Shannon who's not here.
0:41:02 > 0:41:04Having heard what his family thought,
0:41:04 > 0:41:08Jim felt forced to be honest with himself.
0:41:08 > 0:41:10I've characteristics or traits,
0:41:10 > 0:41:14some of which have that a psychopathic, yes.
0:41:15 > 0:41:19I could blow off an aunt's funeral if I thought there was a party that day.
0:41:19 > 0:41:21I would just take off.
0:41:21 > 0:41:22And that's not right.
0:41:22 > 0:41:26The thing is I know that now but I still don't care.
0:41:26 > 0:41:31And so I know something's wrong, but I still don't care.
0:41:34 > 0:41:39I don't know how else to put that, you're in a position where,
0:41:39 > 0:41:41that's not right, I don't give a shit.
0:41:41 > 0:41:42And that's the truth.
0:41:42 > 0:41:45But Jim still had a puzzle to solve.
0:41:45 > 0:41:50If he had the brain and the genes of the killer, why wasn't he one?
0:41:50 > 0:41:55The answer is that whether genes are triggered on not will depend
0:41:55 > 0:41:57on what happens in your childhood.
0:41:57 > 0:42:03Simply having the warrior gene doesn't necessarily mean you'll be violent.
0:42:03 > 0:42:08If you've the high-risk form of the gene and you were abused early on in life,
0:42:08 > 0:42:11your chances of a life of crime are much higher.
0:42:11 > 0:42:15If you have the high-risk gene but you weren't abused,
0:42:15 > 0:42:17then there really wasn't much risk.
0:42:17 > 0:42:22So just a gene by itself, the variant doesn't really dramatically affect behaviour,
0:42:22 > 0:42:25but under certain environmental conditions, a big difference.
0:42:25 > 0:42:28And that was a very profound finding.
0:42:30 > 0:42:35So what was it about Jim's environment that cancelled out his unlucky genes?
0:42:39 > 0:42:42It turns out I had an unbelievably wonderful childhood.
0:42:45 > 0:42:48When I went back to look at old movies and pictures,
0:42:48 > 0:42:51and smiling and as happy as a lark.
0:42:51 > 0:42:54You can see it all the way through my life.
0:42:54 > 0:42:59There's a good chance that offset all these genetic factors,
0:42:59 > 0:43:01the brain development and everything.
0:43:01 > 0:43:02And it washed that away.
0:43:13 > 0:43:19It seems your genes can increase your chances of being a violent psychopath.
0:43:19 > 0:43:24Though it's your environment that shapes whether you'll ever be one.
0:43:24 > 0:43:28But understanding the world of the psychopath is now leading
0:43:28 > 0:43:31scientists beyond the world of prison walls.
0:43:36 > 0:43:39Scientists could be looking for psychopaths in a place near you.
0:43:53 > 0:43:57When you walk in the city, you're not thinking of psychopaths.
0:43:57 > 0:44:02And yet the chances of passing one are higher than you think.
0:44:02 > 0:44:05Psychopaths have been adopting a camouflage,
0:44:05 > 0:44:09taking even the experts by surprise.
0:44:12 > 0:44:15I met my first psychopath a little over 25 years ago.
0:44:17 > 0:44:20And it wasn't someone in a prison,
0:44:20 > 0:44:25it was someone who was working for a company where I was a consultant.
0:44:29 > 0:44:33When I talked to people about it, half thought he was a wonderful leader.
0:44:33 > 0:44:37The other half of the team members felt quite the opposite.
0:44:37 > 0:44:38They thought he was the devil incarnate.
0:44:38 > 0:44:45So I was somewhat puzzled by this and I called Bob Hare,
0:44:45 > 0:44:49and at the end of the conversation he said, yep, you got one.
0:44:50 > 0:44:55When Paul called me and described the characteristics in the people he was dealing with,
0:44:55 > 0:44:58the concept hit me right between the eyes, of course.
0:44:58 > 0:45:01Paul applied Bob's psychopathy checklist,
0:45:01 > 0:45:04and found this leader fitted the profile.
0:45:04 > 0:45:07His high status had hidden the truth.
0:45:07 > 0:45:11Psychopaths really aren't the kind of person you think they are.
0:45:11 > 0:45:14In fact, you could be living with one, married to one
0:45:14 > 0:45:19for 20 years or more and not know that that person is a psychopath.
0:45:22 > 0:45:25In more modern times, we've identified individuals
0:45:25 > 0:45:28who we might label the successful psychopath.
0:45:30 > 0:45:33Whom do you think of when you hear the term psychopath?
0:45:33 > 0:45:37Most likely it's Hannibal Lecter, or some other serial killer.
0:45:37 > 0:45:42But the actual behaviours they engage in will depend upon
0:45:42 > 0:45:44the context, on how bright you are.
0:45:44 > 0:45:47What do you look like? What kind of upbringing have you had?
0:45:47 > 0:45:51Being a psychopath doesn't mean you can't get a job.
0:45:51 > 0:45:54Part of the problem is that the very things we're
0:45:54 > 0:45:59looking for in our leaders, the psychopath can easily mimic.
0:46:02 > 0:46:07Their natural tendency is to be charming.
0:46:07 > 0:46:10Take that charm and couch it in the right business language,
0:46:10 > 0:46:14it sounds like charismatic leadership.
0:46:14 > 0:46:17You think of psychopaths as having at their disposal,
0:46:17 > 0:46:20a very, very large repertoire of behaviours.
0:46:20 > 0:46:28So they can use charm, manipulation, intimidation, whatever is required.
0:46:28 > 0:46:32Psychopaths can also turn their lack of emotion to their advantage.
0:46:32 > 0:46:36The psychopath can actually put themselves inside your skin
0:46:36 > 0:46:38intellectually, not emotionally.
0:46:38 > 0:46:41They can tell what you're thinking in a sense,
0:46:41 > 0:46:44they look at your body language, listen to what you're saying.
0:46:44 > 0:46:47But what they don't really do is feel what you feel.
0:46:47 > 0:46:51What this allows them to do is to use the words to manipulate
0:46:51 > 0:46:54and con and interact with you without the baggage of having
0:46:54 > 0:46:57this, I really feel your pain.
0:47:00 > 0:47:04Paul then constructed his own survey to see how many psychopaths
0:47:04 > 0:47:07had infiltrated big business.
0:47:07 > 0:47:13The answer? Almost four times as many as in the general population.
0:47:13 > 0:47:18These were all individuals who were at the top of an organisation.
0:47:18 > 0:47:24Vice-presidents, directors, CEOs, so it was actually quite a shock.
0:47:24 > 0:47:26But the biggest surprise was
0:47:26 > 0:47:28when they looked at their actual performance.
0:47:29 > 0:47:32The higher the psychopathy, the better they looked.
0:47:32 > 0:47:37These people walked into the room and everybody got excited, watching them, the room lit up.
0:47:37 > 0:47:42Charisma, lots of charisma, and they talked a good line.
0:47:42 > 0:47:44But if you look at their actual performance
0:47:44 > 0:47:49and ratings as a team player and productivity and so forth, dismal.
0:47:49 > 0:47:52Looked good, performed badly.
0:47:52 > 0:47:54And that was really quite a dramatic finding.
0:47:54 > 0:47:58Their ability to communicate, to charm,
0:47:58 > 0:48:02to manipulate those around them overshadowed the hard data.
0:48:05 > 0:48:07Paul thinks this is just the beginning.
0:48:07 > 0:48:11Corporate culture today seems ideal for the psychopath.
0:48:12 > 0:48:16They're thrill-seekers, they're easily bored.
0:48:16 > 0:48:21What better place to work than a place that's constantly changing?
0:48:22 > 0:48:25That's the perfect environment for a psychopath.
0:48:28 > 0:48:32So how do you tell the high-power, high talent MBA
0:48:32 > 0:48:39student from the lying, cheating, deceitful, manipulative psychopath?
0:48:39 > 0:48:40Very, very hard to do.
0:48:47 > 0:48:53So the blend of genes and environment determine not only who will be a psychopath,
0:48:53 > 0:48:58but whether they end up in the boardroom or behind bars.
0:49:00 > 0:49:04Now this new science is about to challenge us all.
0:49:04 > 0:49:09It's about to make us question not only our ideas of good and evil,
0:49:09 > 0:49:13but even of crime and punishment itself.
0:49:17 > 0:49:22I was asking him, "Please." I was begging him to stop.
0:49:22 > 0:49:23SIREN
0:49:25 > 0:49:27And he wouldn't stop.
0:49:28 > 0:49:34In 2006, a brutal murder took place that rocked the state of Tennessee.
0:49:36 > 0:49:38It was a horrible crime.
0:49:39 > 0:49:44Everybody knows that Mr Waldroup had committed a murder.
0:49:46 > 0:49:48He attempted to murder his wife
0:49:48 > 0:49:51and he did murder the friend of his wife.
0:49:51 > 0:49:53And it was done in a very violent way.
0:49:55 > 0:50:01At one point, he had a machete, he ran after her, he cut her.
0:50:01 > 0:50:05So it was a pretty grisly scenario.
0:50:09 > 0:50:13This was the kind of crime where there is no question who did it.
0:50:13 > 0:50:16I killed Leslie Bradshaw.
0:50:18 > 0:50:20I cut my wife.
0:50:21 > 0:50:23In the state of Tennessee,
0:50:23 > 0:50:27that meant Bradley Waldroup was facing the death penalty.
0:50:29 > 0:50:34But in this case, the man who could save Waldroup was not a lawyer,
0:50:34 > 0:50:37but a forensic psychiatrist.
0:50:37 > 0:50:42A fundamental question would lie at the heart of Waldroup's defence.
0:50:42 > 0:50:46He may have done it, but was he to blame?
0:50:46 > 0:50:49I think in the opening statements,
0:50:49 > 0:50:53the defence attorney said that, we are not disputing who did this crime,
0:50:53 > 0:50:56but what we would like to talk about is why it happened.
0:50:58 > 0:51:02Dr Burnet agreed to gather the evidence.
0:51:02 > 0:51:06I first saw Mr Waldroup. We arranged to do an evaluation at Vanderbilt
0:51:06 > 0:51:09and I met him in this room.
0:51:09 > 0:51:12The Sheriff sits on the other side of the window,
0:51:12 > 0:51:16but Mr Waldroup himself was... He's a middle-aged man.
0:51:16 > 0:51:21He's pleasant. He's talkative. He's co-operative.
0:51:21 > 0:51:24In other words, this is a normal-looking man, who is conversant
0:51:24 > 0:51:28and fairly articulate, but who has a story.
0:51:29 > 0:51:33And, in his case, I think the story was very important.
0:51:33 > 0:51:38Waldroup's actions suggested a brutal, destructive personality.
0:51:38 > 0:51:43My initial impression was that this was an unusually violent act.
0:51:43 > 0:51:47This was a murder case and it was also a capital case,
0:51:47 > 0:51:51meaning that the state of Tennessee were seeking the death penalty.
0:51:56 > 0:52:01The evaluation was going to include a new and controversial element.
0:52:02 > 0:52:06Did Bradley Waldroup have the warrior gene?
0:52:12 > 0:52:14After a week or so, we got the result back
0:52:14 > 0:52:18and it was, I guess what one would call a positive result,
0:52:18 > 0:52:24in the sense that he had the low-activity version of the MAOA gene.
0:52:26 > 0:52:30But this gene would only be relevant to his defence
0:52:30 > 0:52:35if he'd also had an extremely difficult early environment.
0:52:36 > 0:52:40The question is, does he have a history of child abuse? And he did.
0:52:42 > 0:52:46Mr Waldroup described times of getting physically disciplined
0:52:46 > 0:52:54where he had welts, he had bruising, and that this was a fairly regular experience for him.
0:52:54 > 0:52:58So we thought that that might be important in court.
0:53:02 > 0:53:04This genetic evidence was so new,
0:53:04 > 0:53:09that Burnet had to work out how he was going to explain it to the jury.
0:53:10 > 0:53:13We basically thought back!
0:53:15 > 0:53:19We didn't get out old textbooks. We did collect pictures.
0:53:19 > 0:53:22We thought that images would be very important.
0:53:22 > 0:53:24We obviously want to keep their attention.
0:53:24 > 0:53:28It can be very boring to be on a jury for several days.
0:53:30 > 0:53:33The DNA evidence revolved around one idea.
0:53:34 > 0:53:41A gene composed of four segments is safe. Three, and you're at risk.
0:53:43 > 0:53:46But would a judge accept this evidence?
0:53:46 > 0:53:48It had never been used in court before.
0:53:54 > 0:53:57The day of the trial arrived.
0:54:02 > 0:54:05I drove down to this small town in Tennessee.
0:54:05 > 0:54:10We were mainly thinking would the judge let us testify about this topic?
0:54:13 > 0:54:17This is what one might call novel science, in that it's a new kind of science.
0:54:19 > 0:54:22We were the first people, as far as I know,
0:54:22 > 0:54:28to introduce this gene environment interaction in a trial.
0:54:29 > 0:54:32Despite strong objections from the prosecution,
0:54:32 > 0:54:36the judge allowed Burnet to take the stand.
0:54:36 > 0:54:40Burnet knew he could be making history.
0:54:41 > 0:54:45The jury is sitting in the court and we're asked to go to and testify one at a time.
0:54:45 > 0:54:51When Penny tried to run, he intentionally drew that weapon up
0:54:51 > 0:54:56and she was running behind that trailer, and fired twice.
0:54:56 > 0:55:00Remember Penny's testimony. She says that is why she got hit in the back.
0:55:00 > 0:55:02That's the best description...
0:55:02 > 0:55:07We were assuming that he would be found guilty of first-degree murder,
0:55:07 > 0:55:09and then the jury would have to decide
0:55:09 > 0:55:13whether he would get the death penalty or something else.
0:55:13 > 0:55:19So we thought the fair outcome would be for them to take it into consideration at that time
0:55:19 > 0:55:21and to not give him the death penalty.
0:55:25 > 0:55:29Burnet had described Waldroup up as a highly troubled man
0:55:29 > 0:55:32with a gene that that made him vulnerable to rage.
0:55:33 > 0:55:35Then, it was over to the jury.
0:55:40 > 0:55:43What actually happened really surprised us.
0:55:43 > 0:55:47This jury, after hearing the testimony,
0:55:47 > 0:55:49did not find him guilty of first-degree murder,
0:55:49 > 0:55:53but found him guilty of voluntary manslaughter.
0:55:53 > 0:55:58So I think the jury was really influenced by the testimony
0:55:58 > 0:56:01regarding behavioural genomics.
0:56:02 > 0:56:06One juror's comments show just how important it was to them.
0:56:07 > 0:56:12- WOMAN:- A diagnosis is a diagnosis. You know. It's there.
0:56:12 > 0:56:14A bad gene is a bad gene.
0:56:14 > 0:56:18I think this testimony did affect whether he would live or die.
0:56:19 > 0:56:23The implications of the verdict are enormous.
0:56:23 > 0:56:27They could rewrite the fundamental rules of crime and punishment.
0:56:30 > 0:56:32So was it right?
0:56:33 > 0:56:36I think we have to be really careful how we state this.
0:56:36 > 0:56:42This increases a person's vulnerability, but it doesn't make the person commit a crime.
0:56:42 > 0:56:43In his particular case,
0:56:43 > 0:56:49I would say that his free will had been diminished.
0:56:49 > 0:56:52I don't think I would ever say it vanished,
0:56:52 > 0:56:55but I think it had been diminished.
0:56:58 > 0:57:02The verdict has set a powerful precedent.
0:57:02 > 0:57:05It's ushering in a brand new era of neuro-law.
0:57:09 > 0:57:12I think there's an avalanche coming.
0:57:12 > 0:57:19There are hundreds or thousands of research projects on behavioural genomics.
0:57:19 > 0:57:24And, I think in 10, 15 years, there will be more information than we have now.
0:57:27 > 0:57:31The new science is starting to explain the basis of good and evil
0:57:31 > 0:57:33and why we are different from each other.
0:57:35 > 0:57:38I am pretty sure if I had not had this very positive environment,
0:57:38 > 0:57:44I would have turned out poorly. I would have been a real behaviour problem
0:57:44 > 0:57:46and I'm pretty sure of that.
0:57:49 > 0:57:53But while this science is giving us more information,
0:57:53 > 0:57:57it's also undermining our certainties.
0:57:57 > 0:58:01Whether we're good or whether we're evil lies partly in our genes
0:58:01 > 0:58:05and partly in our environment.
0:58:05 > 0:58:09But as we don't choose either,
0:58:09 > 0:58:12are we really free to choose at all?
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