Lawyer begins to have moral opinions - the fool (5)
I believe the answer is:
schmo
'the fool' is the definition.
(I've seen this before)
'lawyer begins to have moral opinions' is the wordplay.
'lawyer' becomes 'sc' (I am not sure about this - if you are sure you should believe this answer much more).
'begins to' says to take the initial letters (I've seen 'beginning to' mean this).
The first letters of 'have moral opinions' is 'hmo'.
'sc'+'hmo'='SCHMO'
Can you help me to learn more?
(Other definitions for schmo that I've seen before include "Boring American" , "jerk" , "Inept person (US_informal)" , "Fool (Yiddish)" , "clot" .)