Received wisdom suggests that deeper voices are seen as authoritative and trustworthy. A recent scientific experiment confirms that perception, suggesting that men and women with deeper voices are more likely to succeed in leadership positions.
Here's how the US research team described the process in the journal Proceedings Of The Royal Society B:
Human voice pitch affects how speakers are perceived. As such, does voice pitch affect how we perceive and select our leaders? To answer this question, we recorded men and women saying ‘I urge you to vote for me this November’. Each recording was manipulated digitally to yield a higher- and lower-pitched version of the original. We then asked men and women to vote for either the lower- or higher-pitched version of each voice. Our results show that both men and women select male and female leaders with lower voices. These ﬁndings suggest that men and women with lower-pitched voices may be more successful in obtaining positions of leadership.
Granted, if you have a very high-pitched voice, then you probably won't be able to lower it to Darth Vader-like tones. And since the study didn't incorporate any substantive content -- an element that would influence many people's perception of politicians -- its application to a broader context needs further research. Still, it's a reminder that changing your voice can help persuade people.