The Santa Clara County Open-Space Authority Act established the Santa Clara County Open-Space Authority (OSA) to encourage agricultural activities and to aid in countering the urbanization of land within the County. The Act gave the OSA power to fund the acquisition of open space by levying special assessments, which are compulsory charges levied against real property directly benefitted by a local improvement. To that end the OSA formed an assessment district in 1994.
Voters passed Proposition 218, which changed the law governing special assessments. Prop 218 made special assessments, which are distinct from property taxes, subject to the general requirement that no new tax may be imposed without a two-thirds vote of the electorate. After Prop 218, newly-added article XIII D of the state constitution required that an agency proposing to levy an assessment identify the parcels specifically benefited, the proportional benefit they would receive, and related information.
