Position responsible for the electric chair (3,4)
I believe the answer is:
hot seat
This clue is a double definition.
'position' is the first definition.
(I have seen 'Position of responsibility ' mean 'hot seat' so perhaps 'position' could also mean 'hot seat')
'the electric chair' is the second definition.
(synonyms)
'responsible for' acts as a link.
(Other definitions for hot seat that I've seen before include "from which bottom quick to rise?" , "Uncomfortable or tricky situation (informal)" , "new constituency" , "Chair for person with difficult responsibility" , "Position at top" .)