Firm belief may lead to imprisonment (10)

I believe the answer is:

conviction

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'firm belief' is the definition.
(I've seen this before)

I don't understand the rest of the clue.

(Other definitions for conviction that I've seen before include "Certainty" , "Firm belief" , "that may lead to imprisonment?" , "in being found guilty" , "Strong belief" .)

I've seen this clue in The Globe and Mail.

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