How does one reconcile the idea in modern democracy that every person will be judged purely based on their own actions, with the doctrine of the belief in the state of sin in which humanity exists since the fall of Man?
This is especially relevant with respect to people who lived before the advent of Christianity, where there are no external factors such as the belief in a sacrifical crucifixion to "restore the balance", so to speak (unless a kind of retroactive effect of this on these people is believed in, violating causality).
It is clear that the two principles are logically incompatible with each other, as evidenced by the dogma of total depravity telling us, even in its highly softened Roman Catholic form, that man cannot "be justified before God by his own works, …without the grace of God through Jesus Christ". On the other hand, the Universal Declaration of Human Rights, arguably the foundational document of modern democracy, in Article 11, states that
Everyone charged with a penal offence has the right to be presumed innocent until proved guilty according to law in a public trial at which he has had all the guarantees necessary for his defence.
No one shall be held guilty of any penal offence on account of any act or omission which did not constitute a penal offence, under national or international law, at the time when it was committed. Nor shall a heavier penalty be imposed than the one that was applicable at the time the penal offence was committed.
If it is in fact the case that they cannot be reconciled within the same logically consistent system, in what ways and domains is the subsequent doublethink applied?