There was a really good video clip of a protestor in 2020, paraphrased: "we came out to protest, then the cops started hitting our heads with batons. we started wearing helmets, so they gassed us. We started bringing masks, so they attack us. Now we bring shields and they call them weapons. Someone is escalating this, but it's not us".
Basically, any evidence that you plan to defend yourself gives the cops, in their mind, cause to attack. Since you planned to defend yourself. Except fire. Cops are scared as fuck of fire.