Because the Portugese police didn't know thier arse from thier elbow and decided that a strange man sighted several times at the crime scene didn't warrent investigation. It's probably taken everyone else this long to trawl through the 30k pages of crap they came up with to come up with these eyewitness reports.
The same problem occurred with the boulder police station colorado with the Ramsey case.
I agree with your view of things..The reasons are obvious ..real truths cannot be covered up for TOO LONG...and this has shown to be correct in both cases..
If either family we have mentioned had history or form by any witness /family members/friends/ ect we would know about it.Innocent families actually DO EXIST ..
Sadly the portugese cops are really dumb..I doubt they could complete a crossword puzzle without kfing that up.