Deeper-voiced candidates are more likely to win an election, a new study has found.
The research, published in the open access journal PLoS ONE, found candidates with a deeper voice were more likely to gain votes because they are associated with higher testosterone.
More than 800 people were given two recordings to listen to, with the same individual saying in different pitches:
I urge you to vote for me this November.
After listening to both, participants were asked which voice they would vote for if they were competing in an election. The candidates with deeper voices won 60 to 76 per cent of the votes.
Participants were also asked which voice seemed stronger, more competent, and older - and the researchers found perceived strength and competence mattered more than age did to voters.
The researchers also concluded that this bias was negatively affecting female candidates' chances:
Importantly, here we also found that this bias is strongest in the case of female candidates.
Because voice pitch is highly sexually dimorphic, on average twice as high in women as compared to men, this result suggests that voice pitch may be an impediment to women gaining positions of leadership.
This was a problem that Margaret Thatcher apparently faced. According to the former prime minister’s biographer, Charles Moore, she used speech coaching to lower her voice before becoming leader of the Conservative party.
It's not all bad news though. Casey Klofstad, the study's co-author and associate professor of political science at the University of Miami, said:
Becoming more aware of the biases influencing our behaviour at the polls may help us control them or counteract them if they’re indeed leading us to make poor choices.
The researchers now plan to see if deepness of voice also correlates with years in office or number of bills passed.