I was actually hoping you would have a stab at answering the following two questions in my post:-
(1) WHY are the McCanns so important that SY were told they could not be investigated?
(2) WHY are the McCanns so important that SY would agree to a request which could possibly result in their officers being responsible for perverting the course of justice?
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But not to worry if you can't think of a credible answer. I can't think of one either.
(must go out now)
SY had a remit, the remit was to investigate abduction.
Originally UK Police recommended that the PJ investigate the McCann's, since there was nothing to indicate abduction, and as Sutton is clearly aware, there are inconsistencies in the McCann's and associates version of events.
This was changed to abduction, yet evidence of such an event was clearly lacking.
As to SY, in case it has escaped your attention, they have no powers of arrest in this case. The incident occurred in Portugal.
So, on your return, read what Mr. Sutton has said.
It might help.