Her vote cast against platform for drug trafficking (4-3-7)

I believe the answer is:

over-the-counter

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'platform for drug trafficking' is the definition.
I can't tell whether this defines the answer.

'her vote cast against' is the wordplay.
'cast' is an anagram indicator (letters are dispersed or cast around).
'against' becomes 'counter' ().
'her'+'vote'='hervote'
'hervote' with letters rearranged gives 'overthe'.
'overthe'+'counter'='OVER-THE-COUNTER'

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I've seen this clue in The Independent.

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