A uniform lends a person an identity that strangers may answer before the person speaks.

A uniform speaks first. People respond to the role, ask questions of it, extend trust or suspicion to it, and all of that happens before the person inside has said anything. It is efficient, and it means the individual has to work past a response that was aimed at a category.

When you deal with someone in uniform, address the person once, directly, and see what changes. And if you wear one, notice how much of what comes at you is not about you. Both directions of that are worth knowing.