Sus law is a really mean and unfair rule that used to exist in some places a long time ago. It said that if a police officer saw a person who looked a certain way, they could stop and search them without any good reason. The way someone looked could be things like their race, gender, or even their clothes.
Imagine if you were walking down the street and a police officer stopped you and said they needed to check your bag or pat you down, even though you haven't done anything wrong. That would be really scary and unfair, right? That's how a lot of people felt when the sus law was in place.
Thankfully, sus law isn't around anymore because people stood up and said it wasn't fair. We believe that everyone deserves to be treated equally and with respect, no matter how they look.