I’m not proud of it, but sometimes I tend to swear when things don’t go the way they should. A study at Stanford University has shown that people who regularly use foul language are more honest and sincere than people who don’t. Although swearing and cursing are generally not socially acceptable and is often associated with antisocial behaviour, the positive aspect is that people show more of their true feelings by using bad language.
It also appears that innocent suspects who are interrogated by the police swear more than suspects who turn out to be guilty. They probably need to think a lot more about the story they want to tell and they certainly don’t want to show their true feelings. Although it is not the case that a person who swears a lot is by definition an honest and trustworthy person.
You can read the research on: https://journals.sagepub.com/doi/full/10.1177/1948550616681055