(Partial) credit for citing the correct term (used by the prosecutors) demonstrate rather than prove.
It's a pity the prosecutors didn't add that there was no need for the McCanns to demonstrate their innocence.
Also a pity that they didn't record (even if they did think it) that the disgraceful modus operandi of the PJ's questioning of the McCanns during their arguido interviews (including either incompetent or fraudulent misrepresentation of evidence) left the McCanns ample and justified reason to suspect the motive behind this so-called 'reconstitution' which, in any event, could never have shed light on anything, since you can never recreate in retrospect a sequence of events that have already come to pass in real-time.
Human memory (including honest human memory) is too fallible and unreliable for that.
It wasn't for the McCann's to second guess their interrogators, they should have afforded them the simple courtesy of answering all of their questions and persuaded their friends to actively take part in any reconstruction necessary in order to establish exactly who was where and who did what that night. Thwarting a police enquiry into the disappearance of your own child is a no no in police circles I can assure you.
One question which never seems to get asked is, why didn't the McCann's ask to speak to the head honcho directly?