Judge used same rule in city (9)
I believe the answer is:
jerusalem
'city' is the definition.
(Jerusalem is an example)
'judge used same rule' is the wordplay.
'judge' becomes 'J' (abbreviation for judge).
'used' indicates an anagram.
'same'+'rule'='samerule'
'samerule' is an anagram of 'erusalem'.
'j'+'erusalem'='JERUSALEM'
'in' is the link.
(Other definitions for jerusalem that I've seen before include "Holy city of Muslims, Jews and Christians" , "Knobbly edible tuber" , "Israeli capital" , "disputed city" , "See 17" .)