Observer with the right to check? (4)
I believe the answer is:
seer
'observer' is the definition.
(one who observes or sees)
'right to check?' is the wordplay.
'right' becomes 'r' (abbreviation).
'to' says to put letters next to each other (I've seen this in other clues).
'check?' becomes 'see' ('see' can be a synonym of 'check').
'r' put after 'see' is 'SEER'.
'with the' is the link.
(Other definitions for seer that I've seen before include "Clairvoyant, visionary" , "Person who can read the future" , "Prophet or clairvoyant" , "Soothsayer" , "He forecasts" .)