The most common and most likely answer to this crossword clue is the 12 letter word DISCRIMINATE
I've seen this crossword clue in The Guardian
D
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C
R
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More clues leading to the result DISCRIMINATE
- Record given free airtime when entertaining new single out
- Record speed, about one minute — notice difference
- Be prejudiced minister, cad I fancy
- Discern subtle indirect aims
- Show bias, possibly, as I am in credit
- Judge record speed, about one minute
- Tell apart aims with indirect shot
- Tell apart iced martinis, shaken or stirred
- Discern corrupt indirect aims
- Select police officers put on anti-crime manoeuvre
Buddy explains!

The straight part
We know that "Judge" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case judge = discriminate.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DISCRIMINATE mean?
DISCRIMINATE verb- To make distinctions.
- (construed with against) To make decisions based on prejudice.
- To set apart as being different; to mark as different; to separate from another by discerning differences; to distinguish.
- Having the difference marked; distinguished by certain tokens.