Science and politics: Our inbuilt bias for the deep-voiced leader

In the film The Iron Lady, Margaret Thatcher, played on screen by Meryl Streep, meets with an adviser named Gordon Reece, a former journalist and TV producer.

It's 1975, the year Thatcher became the leader of the Opposition, and Reece wants to alter the image of the candidate he believes could become Britain's first female prime minister.

"You look and sound like a privileged Conservative wife and we've already got her vote," he says. "But the main thing is your voice. It's too high. It has no authority. People don't want to be harangued by a woman or hectored. Persuaded, yes."

Thatcher's admirers were generally not pleased with Hollywood's rendition of the Baroness. But the deliberate modulation of Thatcher's voice is documented in Charles Moore's biography, and the story is better in real life.

Moore describes how voice lessons at Britain's National Theatre deepened Thatcher's tone. "Soon the hectoring tones of the housewife gave way to softer notes and a smoothness that seldom cracked, except under extreme provocation on the floor of the House of Commons."

(The agent who'd arranged the sessions between the theatre's coaches and the leader of the Opposition was the great actor Laurence Olivier whose own voice could probably have cut glass.)

The adjustments to Thatcher's voice may have been a response to the sexism of the time, or to address the class bigotry that dogged Thatcher earlier in her career.

But the Iron Lady's handlers had unwittingly stumbled onto a democratic advantage that is only now being proven scientifically: lower voices get more votes.

Going deep for votes

Cara Tigue is a PhD student in psychology at McMaster University in Hamilton and her research suggests that the pitch of a candidate's voice, how low or high it is, plays a role in the way we vote.

This week on Day 6 we talked about her work, including a study published in the journal Evolution and Human Behaviour.

"Voting behaviour and all of human behaviour is extremely complex," Tigue told me. "There are many factors that play into the decision of who to vote for. And what we're able to show is when we isolate pitch and we manipulate pitch it does change people's perceptions."

Here is how she uncovered that bias. In her lab work, she and her team prepared two versions of the same voice recording of nine U.S. presidents.

Here's a recording of Gerald Ford. And here he is again. 

Both of these recordings have been manipulated, but in the second clip, the voice is slightly deeper.

When subjects listened to the recordings and rated each voice on such qualities as dominance, intelligence and leadership, the deeper voice was the one most said they favoured.

So what qualities did these listeners attribute to lower voices?

"They said they were more dominant, they were more trustworthy. We asked people which voice would you prefer to vote for and overall people chose the lower pitched voices more often.

"We only had one trait that was associated with a higher pitched voice and that was the likelihood of being involved in a government scandal."

Pitch and dominance

Obviously, no one votes for someone simply on the sound of voice alone. It's the values and ideas that are attached to that voice that motivate.

But there are probably qualities and biases that come into play during democratic selection that we don't consciously rationalize when we make our decisions.

In past studies, researchers have measured voter preference in relation to the physical attractiveness of a candidate and the quality of a voice as well. Both of those have been found to play a role.

Tigue's is the first study to try to measure the relationship between voter intention and the pitch of a candidate's voice.

For voters with their own strong ideas, the underlying perceptions surrounding a deep voice probably won't affect them very much. 

But the scenario changes when some sort of threat is introduced.

"The relationship between voice pitch and dominance would more strongly influence voting behaviour in the wartime scenario than in the general national election scenario," Tigue's study says.

In other words, in a flight or fight situation, we imagine the guy with the deeper voice will probably stand his ground. He may not of course, he may be an utter coward.

But our inbred biases tell us —based on nothing more than the pitch of a person's voice — that hanging tough is a reasonable thing to suppose.

Advantage alpha males

Dominance turns out to be a quality we value in a leader. "We think that people trust leaders who would be best able to hold their group together and lead them into battle ancestrally," Tigue says.

"Men who are more dominant tend to have more testosterone and testosterone is connected to the pitch of the voice."

Could that bias be the barrier to women in politics?

In Canada, fewer than one in four federal seats are held by women. Tigue's study has focused on men's voices, but she cites research about women's voices from the University of Miami that's consistent with her findings.

The Miami research showed that women with lower-pitched voices earned roughly 20 per cent more votes than higher-pitched females.

"What's interesting in women's voices is that pitch goes in an opposite way in terms of attractiveness. Higher-pitched voices are perceived as more attractive."

But when choosing a leader, attractive female voices aren't as influential as the ones perceived to be dominant. When she (theatrically) lowered her voice, Margaret Thatcher knew what she was doing.

Battle of the bass

An unanswered question in all this is how do these subterranean biases play out when women are competing directly with men? Like in the current NDP leadership race.

Neither Tigue's study nor the Miami one measures how women's voices stack up against men's in a head-to-head contest.

So when I interviewed Tigue for Day 6, I asked her to listen to the voices of the seven remaining candidates in the NDP leadership race: two women, five men.

Tigue is American and she's busy with her degree so she doesn't follow Canadian politics closely. Once she heard the seven unidentified candidates I asked her which voice appealed to her the most.

She said it was a close call but narrowed it down to two and then finally settled on Nathan Cullen.

I asked her why she liked Cullen's voice. "Purely going on my first impression, I thought it was a warm, trustworthy voice."

Later I asked her if she remembered how many women's voices were among the seven. "Not many", she said. "Maybe two or three?"

Of the two female candidates, neither Peggy Nash nor Niki Ashton was Tigue's second choice.

Becoming an Iron Lady, it seems, takes a lot of work.