Check felon's entourage (9)

I believe the answer is:

constrain

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'check' is the definition.
(constraining is a kind of checking)

'felon's entourage' is the wordplay.
'felon's' becomes 'con's' (abbreviation for 'convict').
'entourage' becomes 'train' (I can't explain this - if you can you should believe this answer much more).
'cons'+'train'='CONSTRAIN'

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(Other definitions for constrain that I've seen before include "Compel towards a course of action" , "Compel - limit" , "Force" , "Check" , "Confine, limit" .)

I've seen this clue in The Telegraph.

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