Criminal on the run casing Conservative Club (9)
I believe the answer is:
truncheon
'club' is the definition.
(type of weapon)
'criminal on the run casing conservative' is the wordplay.
'criminal' indicates an anagram.
'casing' indicates putting letters inside (I've seen this in other clues).
'conservative' becomes 'C' (UK political abbreviation).
'on'+'the'+'run'='ontherun'
'ontherun' anagrammed gives 'trunheon'.
'trunheon' placed around 'c' is 'TRUNCHEON'.
(Other definitions for truncheon that I've seen before include "Peelers' baton" , "Policeman's traditional weapon" , "Police baton" , "Police staff" , "Cosh" .)