That which follows when a retrial is ordered? (7)

I believe the answer is:

trailer

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'that which follows' is the definition.
I can't judge whether this defines the answer.

'a retrial is ordered?' is the wordplay.
'is ordered?' indicates anagramming the letters.
'retrial' with letters rearranged gives 'TRAILER'.

'when' acts as a link.

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(Other definitions for trailer that I've seen before include "It's pulled by a vehicle" , "Advert for film" , "One comes before the big film" , "Mobile home; preview" , "Advertisement for a TV programme" .)

I've seen this clue in the Evening Standard.

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