This kind of DAC is very possible and profitable.
1) People must PAY to submit a dispute to the DAC, some of these fees are paid to the voters and some paid to the share holders.
2) Voting works for binary decisions but how could we use this to settle a divorce?
3) This works well for public disputes, how could it be used in the btc-u hacking dispute?
In a prior life I was working on a centralized debating forum with the aim of finding the truth of anything by having people debate in a new kind of web forum. Recognizing that Republicans and Democrats will fail to apply reason to their votes and instead vote party lines or based upon a biased agenda I knew that I couldn't just have people vote 'true' or 'false' on any given assertion.
So I came up with the idea of having people vote on the relationship between two pieces of information: Does argument A support or contradict argument B. I didn't reveal the result of the votes to the users. The weight I gave a user's vote depended upon how close they were to the mean vote of all other users. In effect, those that were able to correctly guess what others would guess were considered more trustworthy and less biased. Someone with an agenda who voted out of line in an attempt to defy logic would get penalized.
Ultimately the whole system was too complex for people to grasp and I let it die.
That said, JuryShares would be a good way of establishing 'guilt' if you were willing to accept a judgment by random individuals.