Policeman's case for arresting corporal (2,4)

I believe the answer is:

pc plod

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'policeman's' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'case for arresting corporal' is the wordplay.
'case' becomes 'pod' (pod is a kind of case).
'for arresting' is an insertion indicator.
'corporal' becomes 'cpl' (abbreviation).
'pod' placed around 'cpl' is 'PC PLOD'.

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(Another definition for pc plod that I've seen is " Police officer".)

I've seen this clue in The Times.

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