Try to carry on (9)
I believe the answer is:
prosecute
I believe this clue is a double definition.
'try' is the first definition.
(try in a court)
'carry on' is the second definition.
(thesaurus)
'to' is the link.
(Other definitions for prosecute that I've seen before include "Practise" , "Bring before a criminal court" , "Bring a criminal action against" , "Sue" , "Take legal action" .)