r/aita AITA for Calling The Cops on my Best Friend?

Harry Potter - J. K. Rowling
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r/aita AITA for Calling The Cops on my Best Friend?
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Sirius Black on Reddit

r/aita

AITA for Calling The Cops on my Best Friend? 

 I (26M) have a best friend (25M) and a little brother (24M). Recently I found out my best friend (J) has been stalking my brother for years. I found it weird at first but I wasn’t going to get him in trouble or anything unless my brother (R) specifically requested it. 

However after telling J how weird (and perverse) it was to stalk R, he said my relationship with our mutual best friend (RL) was what was weird and perverse. I was more upset about this than the stalking so I ended up calling the cops on him and he’s being held in jail. 

Another mutual friend (25M, P) said I was an asshole for only calling because he made fun of my relationship with RL. But what J was (is??) doing IS illegal so I didn’t really do anything wrong. RL and P both said if I was going to call the cops the reason should’ve been the legality aspect of it and not because he made fun of my relationship. 

So AITA?

EDIT: My brother isn’t aware he was being stalked so I don’t think it makes sense to ask if he’s okay in this situation. 

EDIT 2: If you saw the other post maybe don’t bring up the fact that RL got my cousin pregnant.