Birling is the least 'responsible' for his actions
His inability to admit to his part in the whole drama is a reflection of Priestlys judgement on capitalists
He finds Eva Smiths situation below him and 'awkward'
From the word 'awkward' its evident that Birling shows a lack of responsibility because of his social status. His position in the hierarchy paints life as a perfect picture instead of revealing reality
He calls Eva Smith a 'wretched girl', which highlights his ignorance about people who don't share the same luxurious lifestyle
Its clear that Birling is the centre mouthpiece to emphasise how oblivious capitalists are to the audience.
Sheila
In contrast to her father, Sheila feels the most responsible and guilty for her take in Eva Smiths death
As per the stage directions wish, Sheila looks 'miserably'.
This implies that she shows remorse for her part in Eva Smiths death and is willing to take responsibility for her actions
She asks 'So I'm really responsible?' which clearly says that she is thinking deeply about what she did. Priestly uses this question on purpose, so the audience question themselves about social responsibility
By taking social responsibility , she builds a strong relationship with the Inspector
Priestly tries to imply that the younger audience should follow in Sheila's footsteps by taking social responsibility, as children are the future.
Inspector
The Inspector is a personal body for Priestly to speak to the audience about his views
He is introduced as someone who 'at once creates an impression of massiveness, solidity and purposefulness'
This suggests that the Inspector is omniscient, as he knows how to interrogate each and every family member
Its obvious from the list of three that he is very wise and has a strong sense of responsibility
Later on he is offered a glass of whiskey, but he replies with 'I'm on duty'. This suggests that he knows his responsibility to Eva Smith and he cannot be distracted
He finds each family members part unethical and an abuse of their social authority
In his final speech he talks about being 'members of one body' which is biblical language. Its something Jesus Christ would have said and He is commonly known to have a very strong sense of responsibility
Consequently, the Inspector is believed to be the most responsible character and morally opinionated so is chosen to be the mouthpiece of Priestly's views
Class
Mrs Birling
HOW PRIESTLY PRESENTS IDEAS ABOUT THESE THEMES IN 'AN INSPECTOR CALLS'