"establishing, relating to, or deriving from a standard or norm, especially of behavior."
And other sources have something similar. I'm interpreting your comment as saying "(psychological) harm is subjective, and because it can not be measured empirically, it's not possible to have expertise on this topic."
Fortunately, there are real world consequences that can be measured. If I take an action that makes many people say "ow!" and we acknowledge that expression as an indicator of pain, even though I can't measure the exact level of pain each person is experiencing, I can measure how many people are saying "ow!" I can measure the relationship between the intensity of my action, and the number of people that respond negatively. There's plenty of room for empiricism here, and a whole field of mathematics (statistics) that supports handling "normative" experiences. They even have a distribution for it!
The foundation of law is not scientific exactness or scientific empiricism. It is the mechanism by which a state establishes norms. A law against murder does not stop murder, but it does tell you that society does not appreciate it.