I noticed his jacket looks a lot like an admiral/navy jacket. Do they have any explanation about it or not? Did he go buy a jacket like that, did he steal one from an admiral he beat and sew his symbol in the back?
i don't think so bro.bcz gol d roger had similar red outfit.so that may be the ancient fashion style or oda use that style to give a professional look.
Aw I was kinda hoping maybe their was a fight between him an a big shot admiral and after beating him he stole his jacket as an insult to injury type deal, maybe Garp since he fought Roger a lot and so did Whitebeard.
Probably looks like admirals' coats, but I would say it's just like any captain's coat like Roger's coat for example. Just because it's white it may confuses anyone, yet the inside of the coat isn't like admirals'. There is red inside Whitebeard's coat, so it's better to say it's not same as admirals'