In capital cases, one who advanced an argument for conviction may argue for acquittal, but one who advanced an argument for acquittal may not argue for conviction. He needs to keep thinking through his acquittal arguments till the end. In the final vote, however, he may decide on conviction.
Multiple laws may be derived from one verse, but multiple verses may not be used by the same Sage to derive the same law. Therefore, if two Sages in court bring the same argument citing different verses, it counts as only one vote.
Art: Paulus Berestey, Judge at Haarlem by Frans Hals