They only release them because people believe them. Sounds like diversion tactics.
"Two pieces of information reach us, which we interpret as diversionary tactics with the obvious purpose of diverting suspicion from the McCanns. The first concerns the couple’s active involvement in a campaign to set up an international alert system for missing children. The Policia Judiciaria is approached indirectly through the Department of Criminal Investigation in Portimão and the Directorate in Faro to participate and support the launch of the campaign. We tell the messenger that we are not the appropriate recipients of this enquiry, that the request should be sent to a higher authority, the National Director of the PJ or the Portuguese government.
The second piece of information comes to us from further afield: Beirut, capital of The Lebanon. Imagine this: an Arab shiekh possessed a video of an orgy by other shiekhs on which Madeleine was allegedly recognisable. He would be prepared to hand over this recording to the British Ambassador in exchange for a sum of money to be sent to his lawyer. Once again, we are stupified." (TOTL)