In Australia, for example, e-voting is being used for the elections to the country’s Senate, but the Australian Electoral Commission (AEC) has refused to release the relevant software, despite a Senate motion and a freedom of information request. Being able to examine the code is a fundamental requirement, since there is no way of knowing what “black box” e-voting systems are doing with the votes that are entered.
Source: Australian Electoral Commission Refuses To Allow Researchers To Check E-Voting Software | Techdirt