The most common and most likely answer to this crossword clue is the 7 letter word MORALLY
I've seen this crossword clue in Financial Times
M
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A
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Buddy explains!

The straight part
We know that "in an ethical way" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case in an ethical way = morally.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 MORALLY mean?
MORALLY adverb- In terms of morals or ethics.
- In keeping of requirements of morality.
- To all intents and purposes; practically.