Monitoring lives with unclear broadcast (12)
I believe the answer is:
surveillance
'monitoring' is the definition.
(thesaurus)
'lives with unclear broadcast' is the wordplay.
'with' is a charade indicator (letters next to each other).
'broadcast' indicates an anagram (letters scattered or cast around).
'lives' after 'unclear' is 'unclearlives'.
'unclearlives' is an anagram of 'SURVEILLANCE'.
(Other definitions for surveillance that I've seen before include "Watch" , "Close observation" , "Covert observation" .)