The most common and most likely answer to this crossword clue is the 10 letter word DEFENSIBLE
I've seen this crossword clue in Financial Times
D
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More clues leading to the result DEFENSIBLE
Buddy explains!
The straight part
We know that "can be justified" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case can be justified = defensible.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 DEFENSIBLE mean?
DEFENSIBLE adjective- (of an installation etc) capable of being defended against armed attack
- (of an argument etc) capable of being justified