NSFW How to handle a date rape douche: street justice or the law?

NSFW Say ”Brenda” goes to a party, there are a few people she knows but most she doesn’t. She hangs with ”Derrick” a guy she does know. They did not travel to the party together. There is liquor there, and at some point during the party after a drink ”Derrick” gets for her, she feels woozy. ”Derrick” assures her she just need to walk it off, she finds herself in a back room with him groping her and kissing. In and out of drifting to cloud 9 she remembers telling him she doesn’t want to and to stop, but faintly remembers him pulling her top up and fondling her breast and working her undies off. Hours later she is more or less back on earth and her clothes is askew and a trace of semen on her inner thigh. She goes home troubled, she confides in her close BGF who then rallies the posse. Later one of the girls come on to ”Derrick” and when he believes he is going to get lucky he is led to an empty rest stop where the posse rat packs him. One gal gives him a hand job, then they position his dumbstick on a park table and allow ”Brenda” to whack it with a bat. Then while he is writhing in agony they beat him like the dog the red-headed stop child brought home, pound him like a tent stake, and drop kick him into the middle of the week after next like a puzzle with many missing pieces. Was the street justice enough, wrong, effective, or should they have relied on the law and legal system to gain justice?