You should have reported the upside-down flag to the chief. But you should not have touched it, as it does not belong to you.
You made a poor - yet understandable - choice. Then the firemen made a poor - and dangerous - choice by trying to follow you. I say at this point it’s a draw. Let it be.
Problem is, I had no idea who the flag belonged to when I took it down, and I’m not even sure it was theirs anyway. It wasn’t hanging near the fire house or anything that would give me any reason to believe that they hung it up there (not that I would have ever suspected them anyway). He didn’t indicate that it was his when he demanded it.
I concur.