Punish with prison when a lie's found out (8)

I believe the answer is:

penalise

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'punish' is the definition.
(I know that punish can be written as penalise)

'with prison when a lie's found out' is the wordplay.
'with' is an insertion indicator.
'prison when' becomes 'pena' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'found out' indicates an anagram (discovered out of the normal letter order).
'lies' is an anagram of 'lise'.
'pena' placed inside 'lise' is 'PENALISE'.

Can you help me to learn more?

(Other definitions for penalise that I've seen before include "Perhaps, fine" , "See plain (anag.)" , "Inflict punishment on" , "Disadvantage unfairly" .)

I've seen this clue in the Evening Standard.

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