The most common and most likely answer to this crossword clue is the 12 letter word UNPRINCIPLED
I've seen this crossword clue in The Times
U
N
P
R
I
N
C
I
P
L
E
D
Buddy explains!
The straight part
We know that "without scruples" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case without scruples = unprincipled.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 UNPRINCIPLED mean?
UNPRINCIPLED adjective- Lacking moral values