We make judgements every single day about people. It is a human thing to do and Allah knows this. He tells us when you judge people, judge with justice.
When Allah tells us this, He is not just talking to judges but all of us. Justice is a little bit more than being fair. We will make judgements and other people will make judgements but we have to use justice when we judge people.
We also have to remember just because we are using the law doesn’t mean we are using justice. They always want to win and get what we want. Justice gets put aside. So when we judge people we have to always judge with justice.