I work for a bank and an individual whose bank card had been used fraudulently would NEVER be told to file a police report before taking action. I cannot imagine how clogged up the system would become if everyone who ever has their card information used fraudulently had to file a police report! Our e-banking department deals with this sort of thing on a daily basis.
I've had a credit card used fraudulently and the credit card company contacted me because the transactions were done at stores way out of my normal area (several states away). They verified that I hadn't done the transactions, reversed the charges off the account, closed that account out and opened a new one, and issued me a new card, but not one word was ever said about taking any sort of action to report it to the police.
If your wallet or purse was stolen, then you might want to report that to the police, but it would never be a requirement, or even a request, in order to dispute a transaction and refund the money to your account.
It does make sense, however, that the bank would have to wait until the disputed transaction had actually cleared the account before they could refund the money, because there are all sorts of regulations and rules regarding e-banking that govern that, and you can't actually refund money that hasn't come out of the account yet, even if it shows that the charges on the card are pending.