Retrospectively judge a republican government (3)
I believe the answer is:
raj
'government' is the definition.
(Indian term for rule or government)
'retrospectively judge a republican' is the wordplay.
'retrospectively' says the letters should be written backwards.
'judge' becomes 'j' (abbreviation for judge).
'republican' becomes 'r' (abbreviation).
'j'+'a'+'r'='jar'
'jar' in reverse letter order is 'RAJ'.
(Other definitions for raj that I've seen before include "Indian government" , "Sovereignty" , "Jar (anag.)" , "British dominion over India" , "Indian rule in India" .)