Broadcast poets preclude by legal rule (5)
I believe the answer is:
estop
'preclude by legal rule' is the definition.
'estop' can be an answer for 'preclude' (thesaurus). I am not sure about the 'by legal rule' bit.
'broadcast poets' is the wordplay.
'broadcast' indicates an anagram (letters scattered or cast around).
'poets' anagrammed gives 'ESTOP'.
Can you help me to learn more?
(Other definitions for estop that I've seen before include "Legally prevent" , "Bar, for a lawyer" , "Legally check" , "Legal term" , "Preclude certain evidence (at law) - bar (archaic)" .)