Code of behaviour poor clot broke (8)
I believe the answer is:
protocol
'code of behaviour' is the definition.
(I've seen this before)
'poor clot broke' is the wordplay.
'broke' indicates anagramming the letters.
'poor'+'clot'='poorclot'
'poorclot' is an anagram of 'PROTOCOL'.
(Other definitions for protocol that I've seen before include "Approved procedure" , "Etiquette with regard to rank or status" , "Official code of conduct for a group" , "Diplomatic etiquette or procedure" , "Code of correct conduct" .)