I think it’s a gross breach of trust. In this country witnesses with important information are told that any information they give the police will be treated in strictest confidence. Obviously not in Portugal!
With exceptional circumstances notwithstanding, ALL witnesses in this country must stand in full view of the public and give an account of what they saw,heard. and be available to answer questions under oath (in good faith) from the prosecution, the judge and even jury members (via the judge).
I can't think of any reason why the PJ would not allow, as they do in this country, protection for witnesses under threat. They can also receive anonymous information and add that to the investigation to see where it leads.
I am on the fence as to whether it is a good or bad thing to have the investigation in its entirety placed in the public domain.
With regards to this case; I can fully appreciate why. The McCanns took it global, created a company, and were shown to be unreliable as witnesses to the disappearance of MBM...there was perceived political influence, and vile accusations against the PJ- which still exists to this day by supporters. Getting there side out was a good thing. It should be remembered there was a very large sum of money offered as a reward. no one took that up.