How perponderance of evidence arises is a market.

[gotlucky]

Not every dispute can be resolved by mediation. Some disputes will inevitably turn to violence. In that case, one party can back down, conceding the point to the other party (right or wrong), or they can duel (formally or informally). Logistic Earth wrote a good post about the Zimmerman/Martin case here. I will quote, again, what I believe to be the most relevant part:

@LogisticEarth

Ultimately, I really doubt we’ll ever get enough evidence to either convict or fully vindicate Zimmerman. He was apparently going to be charged with manslaughter, but that lack of evidence caused the state to drop the case. At this point, there’s not much more one can do. Unfortunately, the mob on both sides have formed thier own opinions and seem to be making judgements and accusations about both Martin and Zimmerman.

The bottom line is though, we don’t know precisely what happened, there is not enough evidence to convict or vindicate, and we must leave it at that unless something new comes to light. The only thing one can do is to draw personal insights from the tragedy, about racial prejudices, about the dangers of escalating situations, and rushing to judgements.

Some crimes may go “unsolved”. The thing is, if you cannot prove that a person is guilty, then how do you know if he is guilty. In the case of Zimmerman and Martin, if the prosecutor cannot prove that Zimmerman is guilty of murder, then how can we know if he actually is? We cannot. If Zimmerman were to be okay with a preponderance of evidence, that would be most perplexing.

To now address the apple dispute. If you cannot prove that B stole the apple from A, then how do you know he is guilty? If the apple means that much to A, then he may challenge B to a duel. If it doesn’t, then he can just concede the dispute to B. It is possible that A might want to take his chances with a lower standard of proof, but it is actually B who would have to agree to it, as he is the one being accused. Why would the accused ever agree to a lower burden of proof? It can only mean he would be more likely to lose.

It is for that reason that I find it highly unlikely that preponderance of evidence would arise in a private law society.

@Hefty

When judging if B stole the apple from A, C will have to find that B is not guilty. When judging if A was picking apples from B’s tree, C will have to find that A is not guilty. So C cannot come up with any decision, because there is “reasonable doubt” in either case. Thus A and B are left off where they started. The whole point of the arbitration was for C to make a decision. Clearly they will seek another arbitration, until they find one that will use more lax principles that will advise in favour of one of them.

You need to prove the bolded statement. It is not clear that they will necessarily seek another arbitration. That costs resources, and people do not have unlimited resources to spend towards more arbitration.

PS It is preponderance, not perponderance.