The most common and most likely answer to this crossword clue is the 6 letter word LIABLE
I've seen this crossword clue in The Guardian
L
I
A
B
L
E
More clues leading to the result LIABLE
- Subject to change, bilateral art removed
- . Legally responsible for label about iodine inside
- Prone position with muscle left clenched
- Fifty-one, competent and responsible
- 51 up to it and legally answerable
- Given life, losing heart after temporary release rejected
- Dodgy libel about area being exposed to risk
- Responsible for one in laboratory initially losing Ecstasy
- In Spain the British tacitly ignore the odds, turning responsible
- Likely story about murder victim
Buddy explains!

The straight part
We know that "Subject" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case subject = liable.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 LIABLE mean?
LIABLE adjective- Bound or obliged in law or equity; responsible; answerable.
- Subject; susceptible.
- Exposed to a certain contingency or causality, more or less probable.
- (as predicate, with "to" and an infinitive) likely.