These delegates act only as a mouthpiece for the wishes of their constituency/state and have no autonomy from the constituency only the autonomy to vote for the actual representatives of the state.
This model does not provide representatives the luxury of acting in their own conscience and is bound by imperative mandate.
Essentially, the representative acts as the voice of those who are (literally) not present.
Models of democratic rule making extensive use of the delegate model of representation are often labeled "delegative democracy".
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