Mention criminal group in bar, after reflection (5,2)
I believe the answer is:
bring up
'mention' is the definition.
(I've seen this before)
'criminal group in bar after reflection' is the wordplay.
'criminal group' becomes 'ring'.
'in' is an insertion indicator.
'bar' becomes 'pub' (I've seen this before).
'after reflection' says the letters should be written backwards.
'pub' in reverse letter order is 'bup'.
'ring' inserted inside 'bup' is 'BRING UP'.
(Other definitions for bring up that I've seen before include "Rear like child, or mention for discussion" , "train" , "Raise the issue (in two ways!)" , "Rear, or raise for discussion" , "Lively Baroque dance" .)