Dubious sects up for reorganisation (7)
I believe the answer is:
suspect
'dubious' is the definition.
(I've seen this before)
'sects up for reorganisation' is the wordplay.
'for reorganisation' indicates an anagram.
'sects'+'up'='sectsup'
'sectsup' with letters rearranged gives 'SUSPECT'.
(Other definitions for suspect that I've seen before include "Consider or believe likely" , "Possible perpetrator of a crime" , "Fancy" , "man distrusted?" , "Possibly dangerous or false" .)