Police force have to abandon ship at last (5)
I believe the answer is:
posse
'police force' is the definition.
(posse is a kind of police force)
'to abandon ship at last' is the wordplay.
I cannot quite understand how this works, but
'ship' could be 'ss' and 'ss' is present in the answer.
The remaining letters 'poe' is a valid word which might be clued in a way I don't understand.
This may be the basis of clue (or it may be nonsense).
'have' acts as a link.
Can you help me to learn more?
(Other definitions for posse that I've seen before include "Group supporting sheriff" , "power" , "Sheriff's party" , "Group formed by sheriff" , "Sheriff's assistants" .)