If that is the case, and the guy came up clean but yet still went on to do X, how is Uber any more culpable than a taxi company hiring a cabbie with no record, who subsequently goes out and does X, or a tour company hiring a bus driver with a spotless background, who nonetheless does X?
They aren't. But it seems like there's a new trend in town - when a foreign tech company could potentially have guessed that someone using their service might potentially have done something bad, they're automatically at fault. See: Facebook and Lee Rigby in the UK.
In this case, the logic seems fairly simple - the guy apparently had a prior conviction for rape, thus, should not be allowed to be a taxi driver. If Uber had checked then the rape wouldn't have happened (assuming it did). The problem is the guy's prior conviction was also for raping someone in a taxi cab, so obviously this isn't a solution to all such problems because there's always a first time. Another problem is that I've read India doesn't actually have a national conviction database system, indeed they barely have a coherent national identity scheme at all (I remember reading about programmes to try and introduce biometric identity nationwide to fix this but it's a huge job). Apparently the way you do a background check is walking in to the local police district office and asking. If the crime happened elsewhere, tough luck. For anyone who knows the real situation in India, I'd be interested to know if this is true.
Anyway, even with reliable background checks, you can quickly end up in a situation like the USA where former felons cannot get jobs anywhere (see recent /. story about this problem), and then you get rules like in Europe where former convictions get wiped from the record after a few years to stop that happening, so there are no solutions that make everyone happy.