Time to think logically -- it's a crime (7)
I believe the answer is:
treason
'a crime' is the definition.
(treason is a kind of crime)
'time to think logically' is the wordplay.
'time' becomes 't'.
'to think logically' becomes 'reason' ('reason' can be a synonym of 'think logically').
't'+'reason'='TREASON'
'it's' acts as a link.
(Other definitions for treason that I've seen before include "Crime of disloyalty" , "Serious crime" , "LEse-majestE" , "Offence against state" , "Betrayal (of one's country)" .)