Go ahead: take legal action! (7)
I believe the answer is:
proceed
This clue could be a double definition.
'go ahead' is the first definition.
(I've seen this before)
'take legal action' is the second definition.
'proceed' can be an answer for 'take' (thesaurus). I am unsure of the 'legal action' bit.
Can you help me to learn more?
(Other definitions for proceed that I've seen before include "Continue, carry on" , "Continue; advance" , "Go forward" , "Move forward" , "Follow a certain course" .)