Angrily remands wrongdoers. Art teachers do it nastily (5,3,4,3)

I believe the answer is:

reads the riot act

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'angrily remands wrongdoers' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'art teachers do it nastily' is the wordplay.
'nastily' indicates anagramming the letters.
'art'+'teachers'+'do'+'it'='artteachersdoit'
'artteachersdoit' with letters rearranged gives 'READS THE RIOT ACT'.

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I've seen this clue in the Sydney Morning Herald.

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