Private law is basically the Mafia. It exists. You pay Don X to protect you- to enforce black market contracts, to punish thieves, to do little favours and so on. In return, the Mafia has all the power. The merit principle doesn't apply, because every job is a gift. And it's very violent. It doesn't work at all like glibertarians say it would.
As a smart person once said about Milton Friedman- the real weakness with his ideas is that they have been tried.
Huh. I always thought private law would lead more to like something out of an Old West style Pinkertons. Those who could afford law and security would hire a "police force" to enforce the laws as they (the monied class) deemed fit.