In some democracies, citizens use the initiative and referendum to participate with the legislature in making laws under certain conditions specified by the constitution. The initiative is the right of citizens to propose a law or a constitutional amendment either directly for public vote, or via a vote of the legislature through the submission of a petition signed by a requisite number of eligible voters. The initiative is a means by which citizens can place items directly on the lawmaking agenda or force their representatives in government to consider the matter.
John Patrick, Understanding Democracy, A Hip Pocket Guide