Hrm...I didn't really consider that. Can you elaborate on the destructiveness of peer relationships in the adult world (no elaboration is really necessary when it comes to schoolkids

), particularly compared to the destructiveness of unequal heirarchical relationships? Keeping in mind that juries should decide pretty much everything of importance, part of the reason I'm not terribly concerned here is because any particular court would have a lot of incentive to follow the law faithfully: After all, every court would want customers to do business with it instead of competitors. Still, I could always be wrong. We all pretty much all know how Constitutional republics go: They start off small, and depending on how strong the Constitutional checks and balances are, they either resist growth or allow creeping growth until emerging into a full-blown leviathan state. In contrast, I look at anarcho-capitalism as more of an ambitious experiment with a lot of unknown variables. It's kind of the devil we don't know, since it hasn't been tried before in modern times as far as I know...although anarchy in Celtic Ireland was somewhat similar and supposedly worked very well, and there are other historical examples of anarchy without chaos too.
The "peer review" thing - which is little more than my best guess about the way things could be done or might work out naturally - is really just something that would come into play in the appeals process. If some one-sided rogue court kept butchering trials and getting overturned by other courts, fewer and fewer customers would trust it with their money and their fates. The public would start to consider it a kangaroo court, and it would get to the point where everyone just routinely ignored its decisions as if they never happened, including other courts. This kind of negative peer review would effectively strip a kangaroo court of any "moral authority" it ever had to compel people to follow its judgments. Sure, such a one-sided court would still have customers for a while - the ones who know they will probably win no matter what.

However, once a more respected court overturned that court's judgment on appeal, it would probably require the customer who won in that court (but lost the appeal) to reimburse their trial opponent for the costs of that wasted trial. Soon after, the kangaroo court would simply die out, because even the preordained winners would recognize the fruitlessness of choosing that court.
Ultimately, the real power would reside with the public (the "customers"). If things ever really got out of control and the courts all became corrupt and disrespected - and somehow no new trustworthy court entered the market that people actually trusted, respected, and flocked to (no matter how much some corrupt court tried to overturn its decisions) - then everyone involved in the corruption would likely have to fear for their heads. In a world where people did not cower before or worship an almighty state, I don't think the people would be terribly likely to respect/help enforce any corrupt court's decision to imprison the vigilante who decided to start "cleaning up house."
That's just my assessment though, and I definitely understand people's reluctance to even contemplate trying something so radically different. Some minarchists believe anarcho-capitalism couldn't ever work, and some anarcho-capitalists believe trying to keep government limited is unavoidably an exercise in futility...personally, I think both are probably viable options, if "done right."
I think you're right, and I was actually pretty surprised when I saw it missing from the option list myself.