Highlights The decision structures aggregate the opinions of voters on several dimensions. Characterization of weighted multi-dimensional rules is provided. Some multi-dimensional rules are represented by a combination of single dimension rules. Links to the referendum paradox and the Ostrogorski paradox are made.AbstractThis paper deals with rules that specify the collective acceptance or rejection of a proposal with several dimensions. We introduce the notions of separability and weightedness in this context. We provide a partial characterization of separable rules and show the independence between separability and weightedness.