this theme is represented through Inspector Goole because all the other characters show no morally good decisions before the Inspector interrupts their night and attempts to change the characters morals
however Mr and Mrs Birling show no changes in morals which means that the inspector has no moral authority over them as he cant help them to change their minds and realise how they have been bad people
Sheila and Eric do show change in morals which shows how the Inspector does have moral authority however it is dependent on whether the characters are remorseful and show willingness to change their behavior for the better in the future