Why courts tape abuse - be careful! (5,4,4)

I believe the answer is:

watch your step

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'careful' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.

'why courts tape abuse' is the wordplay.
'abuse' indicates an anagram.
'why'+'courts'+'tape'='whycourtstape'
'whycourtstape' anagrammed gives 'WATCH YOUR STEP'.

'be' is the link.

Can you help me to learn more?

I've seen this clue in The Guardian.

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