The security check has at least one major flaw. Since you don't have to prove who you are to a member of the police etc, then all the disclosure can say is that the person with this name hasn't got any priors. The security check as done by the NSW (Australia) Police require you to turn up with your docs and get fingerprinted.
As far as I know, it doesn't search over seas either. (I could be wrong on this one)