Office equipment shown by policeman? That is right (6)
I believe the answer is:
copier
'office equipment' is the definition.
(I've seen this before)
'shown by policeman? that is right' is the wordplay.
'shown by' says to put letters next to each other.
'policeman?' becomes 'cop' (cop is a kind of policeman).
'that is' becomes 'ie' ('i.e.' can be a synonym of 'that is').
'right' becomes 'r' (common abbreviation).
'cop' next to 'ie' is 'copie'.
'copie'+'r'='COPIER'
(Other definitions for copier that I've seen before include "unoriginal type" , "Machine for making facsimiles" , "Duplicator" , "Machine for reproducing something" , "Office machine" .)