In principle, you're right
Unfortunately, an environment of abuse does not uphold "innocent until proven guilty". Baseless accusations of the dominated by the dominant, especially when made loudly and in public, constitute instant damnation...
...and that's in modern Western Civ - now transfer that concept to a traditional Middle Eastern culture (cf. the "Old Testament"), and you get multiple repetitions of Mary Anne's little playlet. In other words, the secret ballot protects the voter for only as long as the curtain is closed.