Judge moving targets and aim (10)
I believe the answer is:
magistrate
'judge' is the definition.
('magistrate' can be a synonym of 'judge')
'moving targets and aim' is the wordplay.
'moving' is an anagram indicator.
'and' means one lot of letters go next to another (I've seen this in other clues).
'targets' after 'aim' is 'aimtargets'.
'aimtargets' with letters rearranged gives 'MAGISTRATE'.
(Other definitions for magistrate that I've seen before include "Justice of the peace" , "Dispenser of justice" , "your worship" , "one on the bench" , "Court head" .)