Bird in cage: crime considering that won't open (7,3)

I believe the answer is:

battery hen

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'bird in cage' is the definition.
I know nothing about this answer so I cannot judge whether this works.

'crime considering that won't open' is the wordplay.
'crime' becomes 'battery' (battery is a kind of crime).
'considering that' becomes 'when' (I've seen this in another clue).
'won't open' means to remove the first letter.
'when' with its first letter taken off is 'hen'.
'battery'+'hen'='BATTERY HEN'

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I've seen this clue in The Times.

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