I also bought an iPhone 5s from a police auction with icloud lock, it also had a phone number to call if you found it...I called the number which was in Indonesia and spoke to a woman who confirmed that her husband was from the UK and she would get him to call me..He never did...These are the steps I have taken to try and get the phone removed from icloud lock..
1.Talked to the police....They confirmed that I now owned the phone.
2.Talked to my solicitor...who confirmed that I now owned the phone.
3.Rang apple ..Very nice on phone..Told me to go to apple store with paperwork.
4..Went to apple store with paperwork...No interest.. just told me to ring apple support.
5..Rang apple support..put through to the security team..Very nice man told me this was very unusual but could do nothing for me.
So after all that I have a iPhone which I legally own but can not use...
Icloud lock is a very good idea if you have your phone stolen....But because of apples policies it is also a great for criminals to stop there phones benefiting anyone else after there they have been caught.
Are the Police cheating the public by selling phones that cant be used?....I think so.
Are apple helping protect criminal assets?....probably not, but they are stopping it being used.