Criminal making fellow pressure coppers (5)
I believe the answer is:
pence
'coppers' is the definition.
(copper can mean a penny coin)
I cannot understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for pence that I've seen before include "Small-value coins" , "Fractions of a pound" , "Small coppers" , "Small sum of money" , "some European capital" .)