Be ill disposed to commit an offence (5)
I believe the answer is:
libel
'offence' is the definition.
(I've seen this before)
'be ill disposed' is the wordplay.
'disposed' indicates an anagram.
'be'+'ill'='beill'
'beill' with letters rearranged gives 'LIBEL'.
'to commit an' is the link.
This may not be correct. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for libel that I've seen before include "Crime of publishing false statement that damages reputation" , "Defamatory publication" , "Damaging publication" , "Calumny" , "Slanderous statements in print" .)