Heavy-handed Congress obstructing writer from the south (5)
I believe the answer is:
inept
'heavy-handed' is the definition.
(thesaurus)
'obstructing writer from the south' is the wordplay.
'obstructing' means one lot of letters goes inside another (inserted letters interrupt or obstruct the word).
'writer' becomes 'I' (the person who is writing these clues).
'from' means one lot of letters go next to another.
'the' becomes 't' (the is pronounced as a 't' sound in some dialects).
'south' becomes 'nep' (I can't justify this - if you can you should give a lot more credence to this answer).
'i'+'t'='it'
'it' placed around 'nep' is 'INEPT'.
'congress' is the link.
I am not very happy about this link. It may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for inept that I've seen before include "Clumsy, bungling" , "Cack-handed" , "Awkward, showing no skill" , "Incompetent or gauche" , "Wanting" .)