The most common and most likely answer to this crossword clue is the 8 letter word KIDOLOGY
I've seen this crossword clue in Financial Times
K
I
D
O
L
O
G
Y
More clues leading to the result KIDOLOGY
Buddy explains!

The straight part
We know that "Deception" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case deception = kidology.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 KIDOLOGY mean?
KIDOLOGY noun- The art of kidding, teasing mocking.
- Studied deception.