I'm not talking about fraud. I'm talking about an ordinary wife and mother whose child is seen by some nut who decides it looks like Madeleine Mccann and tells the police. The police have to check it out, but once the mother gives reasonable proof, that should be that.
Interesting you should describe a person who sees a child resembling a reported missing child as "some nut" if that person performs their duty as a citizen and reports the sighting.
What do you consider is reasonable proof? As we have seen documentation can be forged.
What if your ordinary wife and mother does indeed have her child's birth certificate and reasonable proof ... but what if birth certificate and photograph albums etc don't actually feature the child she has substituted for her own?
Glad you seem to accept the police should investigate ... interesting that you don't seem to think it appropriate for them to investigate further than acceptance of the word of a person who may not be all that she seems.