"Moral suasion" refers to the use of persuasion, moral arguments, or social pressure to convince someone to do the right thing or behave morally, instead of using force or laws. Full definition
Our key to success is the use of moral suasion --- persuading our governments to do the right thing. (slaw.ca)
Not something that would happen by moral suasion alone, but it would scarcely be equivalent to imposing martial law. (johnquiggin.com)
The note used moral suasion to discourage the bully, without making it an academic disciplinary matter, and without us needing to know their identity. (slaw.ca)