Procedure - A referendum on a law already passed by the legislature may be requested by petition within 90 days after the law has been filed with the secretary of state. It may not be requested on an emergency law, tax levy or appropriations for current expenses. Signatures of six percent of the electors voting in the last gubernatorial election are required on the petition and must be obtained in at least 44 of the 88 counties. The law is submitted to the voters at the next general election 60 days after the petition if filed and cannot become effective unless approved by a majority of the voters.
--information from the League of Women Voters.