While most people would agree
>>2 is a good option. I'll just state what repercussions it would bring.
Self-esteem. Your brother would subconsciously think that running away is always the solution. "Even my brother could even only report them, how much more me." It would also affect his confidence in you which will also affect him. A minus to esteem is the price to pay for every run-away.
Though there are indeed times where reporting to the police is the only option (the situation really do depend on a lot of factors). But reciprocating with equal ferocity is not always bad.
However as much as possible do
>>2.