Lacking good judgment, mad using dinner to welcome leader of Conservatives (12)

I believe the answer is:

undiscerning

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'lacking good judgment mad using dinner to welcome leader of conservatives' is the definition.
I can't tell whether this defines the answer.

'mad using dinner to welcome leader of conservatives' is the wordplay.
'mad' is an anagram indicator.
'to welcome' is an insertion indicator (in sense of 'inviting in').
'leader of' suggests taking the first letters.
The first letter of 'conservatives' is 'c'.
'using'+'dinner'='usingdinner'
'usingdinner' with letters rearranged gives 'undiserning'.
'undiserning' going around 'c' is 'UNDISCERNING'.

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I've seen this clue in The Telegraph.

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