dont expect much from this forum, the people that can help are only here to fish for clients $.
professional standards command, pretty much are police that investigate themselves. you will find plenty evidence online about how fair people think they are with investigation outcomes.
there a point to make the complaint, to make the record on the system. even if nothing comes of it. it exists maybe to help the next person.
if you are looking for something more, you may want to try talk to a police accountability lawyer.
what is an unlawful arrest? police have a tool box full of loop holes to suit the agenda they have, and cover them in these cases. it all comes down to the details and what you can prove with out doubt, and then what?
if you want your private details, like prints, pictures etc removed form the system thats another issue to look into, like what the rules are, but they may just say you consented so they could, you are not dealing with a level playing field.
i would expect someone made a report to police, that would be on file. there may be something in that amounting to making a false complaint.
