He may be found in a wrongful act (5)
I believe the answer is:
cheat
'he may be found in a wrongful act' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'he may be found in a wrongful act' is the wordplay.
'may be found in' means one lot of letters goes inside another.
'a wrongful' is an anagram indicator (I've seen this in other clues).
'act' with letters rearranged gives 'cat'.
'he' placed within 'cat' is 'CHEAT'.
Can you help me to learn more?
(Other definitions for cheat that I've seen before include "22 [FRAUDSTER]" , "Welsh" , "Dishonest person" , "Play dishonestly" , "Fool" .)