Island's crime associated with crack or Ecstasy (9)
I believe the answer is:
singapore
'island's' is the definition.
(island nation)
'crime associated with crack or ecstasy' is the wordplay.
'crime' becomes 'sin'.
'associated with' means one lot of letters go next to another.
'crack' becomes 'gap' (synonyms).
'ecstasy' becomes 'E' (informal term for the drug).
'sin'+'gap'+'or'+'e'='SINGAPORE'
(Other definitions for singapore that I've seen before include "Far-Eastern state" , "Island nation once a British crown colony" , "Small country of southeast Asia" , "part of Asia" , "Asian republic" .)