Why are so many bosses psychopaths? Scientist claims our stone age brains prefer people who look as if they could fight off a sabre tooth tiger

Have you ever railed at corrupt politicians or megalomaniac business leaders? Are there times when you think your boss is selfish, power-hungry or even a bona fide psychopath?

So often the people in charge of us seem ill-suited to the responsibilities they hold.

I’ve spent decades looking at these questions. I’ve explored who gets power, why they get it and how they behave when they achieve it.

Is it, as the old adage would tell us, that power corrupts? Well, possibly, but I’ve had my doubts.

Another, more troubling, thought has been gnawing at me instead – that something much bigger and more serious is lurking beneath the waves. That power-hungry narcissists are actively seeking out positions that give them control over others.

Such people certainly appear to be well represented in positions of leadership, from the highest offices of state down to the most junior roles in company management. More worryingly still, for deep evolutionary reasons, the rest of us do our very best to help them achieve the power they then abuse.

The pretend prison guards who abused their pretend prisoners

A notorious psychological experiment from the 1970s helps make the point. Researchers at Stanford University in California recruited a group of men and told half of them they were ‘guards’, the other half ‘prisoners. The results were dramatic.

No sooner were the guards handed control than they began abusing the prisoners, attacking them with fire extinguishers, forcing them to sleep on concrete floors and humiliating them.

So bad was the abuse that the experiment was ended early. When the findings were published, they shocked the world.

The evidence seemed all too clear: there are demons within all of us and that positions of authority set those demons free.

But consider this. To find their volunteers, researchers had placed newspaper adverts headed: ‘Male college students needed for a psychological study of prison life.’

Could the wording have skewed the sample of people taking part? When, in 2007, academics looked into this, they found a curious result. It turned out that people who respond to adverts containing the word ‘prison’ are not the same as those who respond to similar adverts that refer to psychological studies.

In fact, those who were drawn in by the word ‘prison’ scored significantly higher on measures of aggressiveness, authoritarianism, Machiavellianism, narcissism and social dominance and significantly lower on empathy and altruism.

It raises a fascinating question – while we always assumed that power corrupts, is it possible that corrupt and corruptible people seek out power? That power isn’t a force that turns good people bad, but a magnet that attracts bad people?

Spotting corruption with the roll of a dice

A study in India recruited hundreds of students and asked them to play a simple game: roll a dice 42 times and record the results.

Before they played, however, the students were told they’d be paid more if they rolled higher numbers. Some students cheated wholesale – the number six was recorded 25 per cent of the time, while the number one was recorded only ten per cent of the time. A few students were even so brazen as to claim they had rolled sixes 42 times in a row.

But there was a twist: the cheats had different career aspirations from those who reported scores honestly. Those with bogus high scores were much more likely to aspire to join India’s notoriously corrupt civil service.

When another team of researchers ran a similar experiment in Denmark, a country where the civil service is clean and transparent, the results were inverted. It was the honest students who wanted to be civil servants. The liars sought professions that could make them filthy rich.

Even five-year-olds love a strong man

Why do we let it happen? Why are corrupt narcissists so frequently in senior roles?

It is partly because our idea of what makes a good leader is ingrained from our earliest years. In one Swiss study, children aged five to 13 were asked to play a computer game in which they picked a captain for an imaginary ship based on two faces on screen.

What the children didn’t know was that the two captains weren’t random – the faces belonged to the winner and runner-up politicians in recent French parliamentary elections.

Staggeringly, 71 per cent of the time the children picked the candidate who had won the election.

The same experiment conducted with adults gave nearly identical results.

Who looks the part, in other words, is an essential part of how we pick our leaders. Some of this is a matter of culture, but across the world the evidence is clear: tall, strong, over-confident men have an advantage.

…And for that we can blame our ancestors

Part of the problem, it seems, is that our brains haven’t changed since the Stone Age. In that time there have been roughly 8,000 generations, and about 7,980 of them have lived in societies in which size and strength were major advantages.

Our brains are wired to favour people who look like they might be good at fending off sabre-tooth tigers or hunting gazelles.

Our world has changed but our brains haven’t. Combine those Stone Age biases with modern-day racism and sexism, and it makes the problem even worse.

Short men struggle, too. More than 2,000 years ago, Alexander the Great granted an audience to the captured Persian queen Sisygambis. Alexander was accompanied by his best friend, Hephaestion, who was taller. Immediately, Sisygambis knelt before Hephaestion to plead for her life, mistakenly assuming that the taller man was the king.

Height was believed to be a pretty good predictor of status then and it is now. American presidents are consistently taller than men of their time. Taller presidents also have a higher chance of being re-elected.

And it’s not just height that affects our judgment. All human faces can be scored by how baby-faced they appear. There’s evidence, for example, that judges and juries treat baby-faced defendants as less culpable for their actions. Political or business leaders with baby faces, meanwhile, may be seen as weak.