Leader dissociated from lies, potentially, in publication (5)
I believe the answer is:
issue
'publication' is the definition.
(I know that publication can be written as issue)
'leader dissociated from lies potentially' is the wordplay.
'leader dissociated from' means to remove the first letter.
'lies potentially' becomes 'tissue' (as in a tissue of lies).
'tissue' with its first letter taken away is 'ISSUE'.
'in' is the link.
(Other definitions for issue that I've seen before include "Supply" , "Circulate, distribute or equip with" , "Bone of contention" , "hot potato?" , "Matter, point" .)