That doesn't make sense. The Portuguese shelved the case in favour of Germany. And then reopened the case.
EXCLUSIVE: BRAVE WPC CONFIRMS UNT FOR ‘BLONDE ACCOMPLICE’ OF MADDIE SUSPECT CHRISTIAN BRUECKNER
It came after she arrested Brueckner in a children’s park during a local fiesta
Jon Clarke – 8Sep 2021https://www.theolivepress.es/spain-news/2021/09/08/exclusive-brave-wpc-confirms-hunt-for-blonde-accomplice-of-maddie-suspect-christian-brueckner/Interesting that it is affirmed that Brueckner was accompanied very much along the lines of the two blonde males seen by witnesses in 2007: this time by a trained observer capable of recognising Brueckner as she describes in the newspaper article and Jon Clarke's book.
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To answer your post Eleanor.
I think the Portuguese did follow it through, perhaps to the extent of getting information about Brueckner from the Germans. But at German behest left the investigation to them. They might even have been investigating Angela's rape at the time and by 2017 suspicions regarding Madeleine might have been arising.
So on the face of it the Portuguese might have seemed remiss ~ but who knows what might have been rumbling behind the scenes in Portugal?
Angla's rape wasn't tried until 2019 and given the tortoise alacrity inter force (and international) investigations proceed at, must have been a long time in putting the evidence together.
Officer Vanessa Veira was working when Madeleine vanished and there may have been higher ups still with an interest too.