Didn't BTCJam requires you to upload a copy of your passport ID card? And they have an international arbitrage too but I don't know if a country's jurisdiction would cover this up.
Basically the higher someone's rating is that means the more he has submitted document for verification or has a good track record of returning the loan. However if someone decided to scam, all BTCjam will give you is an arbitration award that contains all the documents that has been submitted by the person. you will then need to
sue this person at your own will with your own expenses as well