Discard juvenile’s case — it’s not illegal (8)
I believe the answer is:
jettison
'discard' is the definition.
(jettisoning is a kind of discarding)
'juvenile's case it's not illegal' is the wordplay.
'case' says to hollow out the word (remove centre letters).
'illegal' indicates an anagram (the letters ordered wrongly or 'illegally').
'juvenile' with its centre removed is 'je'.
'its'+'not'='itsnot'
'itsnot' is an anagram of 'ttison'.
'je'+'ttison'='JETTISON'
(Other definitions for jettison that I've seen before include "'Throw away, cast overboard (8)'" , "Abandon or throw overboard" , "Abandon, discard" , "Chuck overboard" , "21 [OFFLOAD]" .)