I mean, if we want to be endlessly reductive, we can go back to their origins before Christianity even existed to the Roman Code and the Twelve Tables. They're secular now, and have been for centuries, which is the point I'm driving at. I don't see any priests meting out justice in the courts. And when you bring up the US, you cite the Declaration of Independence only, which is not the basis for our laws. The Constitution explicitly states that Justice is established by the People, not God, and forbids the government from endorsing religion or enacting religiously-minded law.