Definition – A referendum is a general vote by the citizens of a city, region or nation on a single political question which has been referred to them for direct decision.
Relevance to SUMP – Public authorities may decide that decisions relating to the SUMP strategy or specific measures should be put directly in the hands of citizens by holding a democratic referendum. A referendum may therefore form part of a SUMP communication and engagement strategy, which would represent a powerful form of participation. Within the theoretical framework of levels of public participation (Arnstein, 1969), a referendum would be a form of citizen control. Examples of where referenda have been held in relation to a mobility planning issue are the Stockholm, Edinburgh and Manchester congestion charging proposals.
Source: Oxford Dictionaries (online); Arnstein, 1969