Peers slam old report that's recycled (5,8)
I believe the answer is:
lords temporal
'peers' is the definition.
(group of peers in the House of Lords)
'slam old report that's recycled' is the wordplay.
'that's recycled' indicates anagramming the letters.
'slam'+'old'+'report'='slamoldreport'
'slamoldreport' with letters rearranged gives 'LORDS TEMPORAL'.
(Other definitions for lords temporal that I've seen before include "They're entitled" , "certain peers" , "Group of peers" .)