You are happy that he killed 2 people arent you....you seem to take great joy that he shot 2 people dead as though he was some innocent bystander...
Issue with criminal law is the bar is really high to get a conviction..just ask the OJ prosecution team

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Since all we see is kyle being attacked we dont know what led up to it or his role because 2 key witnesses are dead.
What if we found video with kyle pointing his weapon at people walking by... the facts in this case are incomplete and DA did a really horrible job.
The law is not trying to encourage children to go into tense situations with a loaded rifle and take matters into their own hands. Next we will have some nutcase going to a trump rally with a weapon and when he gets attacked he will open fire and claim Rittenhouse defense and he will get off.
This case is not good for anyone to be happy about and acquittal does not end the story for what happened that night.
The families can bring a civil.case against Kyle and will.most likely win a negligence standard (same as OJ).