Bear devouring unruly lad as punishment (4,6)
I believe the answer is:
hard labour
'punishment' is the definition.
(I've seen this before)
'bear devouring unruly lad' is the wordplay.
'bear' becomes 'harbour' (I've seen this before).
'devouring' is an insertion indicator.
'unruly' indicates an anagram.
'lad' is an anagram of 'dla'.
'harbour' placed around 'dla' is 'HARD LABOUR'.
'as' acts as a link.
(Other definitions for hard labour that I've seen before include "Addition to sentence no longer" , "Heavy manual work as punishment" , "Old-fashioned sentence" .)