Is UK equipment being used against US protestors?
We don’t know if other UK equipment has been used. It requires someone to have seen and recorded the equipment in situ, and for it then to have been identified (either at the time or once images and information have been shared).
The use of UK-manufactured anti-protest weaponry has been identified in a number of countries. However, as the US produces a lot of such equipment domestically, this has been mainly used. Even if UK equipment was deployed, it may not be observed and identified.
However, in terms of UK government licensing, evidence of specific use shouldn’t be required for the licence to be revoked or for other licences to be refused. A “clear risk that the items might be used for internal repression” should be sufficient. (Also see FAQ – rigorous export controls?)
If you want to identify equipment, RiotID is a good place to start.