Dodgy American pastor's leader in religious group (7)
I believe the answer is:
suspect
'dodgy' is the definition.
(I know that dodgy can be written as suspect)
'american pastor's leader in religious group' is the wordplay.
'american' becomes 'US' (United States).
'leader' indicates taking the first letters.
'in' means one lot of letters goes inside another.
'religious group' becomes 'sect' (eg a religious sect).
The first letter of 'pastors' is 'p'.
'us'+'p'='usp'
'usp' inserted into 'sect' is 'SUSPECT'.
(Other definitions for suspect that I've seen before include "Believe without being certain" , "Believe (someone) guilty" , "Presume" , "Have qualms about" , "Believe to be guilty, but without proof" .)