Critical attorney, new in dynasty (7)

I believe the answer is:

damning

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'critical' is the definition.
Both the definition and answer are adjectives. Maybe you can see an association between them that I can't see?

'attorney new in dynasty' is the wordplay.
'attorney' becomes 'DA' (District Attorney).
'new' becomes 'n' (common abbreviation eg NT for New Testament).
'in' is an insertion indicator.
'dynasty' becomes 'ming' (Chinese dynasty).
'n' inserted into 'ming' is 'mning'.
'da'+'mning'='DAMNING'

Can you help me to learn more?

(Other definitions for damning that I've seen before include "incriminating" , "Highly critical" .)

I've seen this clue in The Daily Express.

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