To unlock this achievement, you need to do 10 Non-lethal takedowns on criminals in single-player.
In Battlefield: Hardline there are two types of non-lethal takedowns you can do. I recommend this one, walk and sneak up to an enemy or a group of 2 or 3 and show your badge to them, aiming a gun at them afterwards. Another way will be using the T62 CEW (a taser), simply walk up to an enemy or a group of 2 or 3 and incapacitate all of them.
This achievement is best done during Episode 1, though can be gotten through natural progression or arresting warrants.