Ballotpedia completed an inventory of all Oregon ballot measures since 1900. Oregon voters decided on 881 ballot measures between 1900 and 2024—defeating over 53% of them. Four hundred eleven (411) measures were approved, and four hundred seventy (470) measures were defeated. Of the 881 ballot measures, 14 were decided by less than a percentage point of the vote.

In Oregon, citizens have the power to initiate constitutional amendments, state statutes, and veto referendums. Oregon adopted the initiative and referendum process in 1902 with 91.63% of voters supporting the amendment. Oregon was the third state to adopt it behind South Dakota and Utah.

In Oregon, the state legislature has the power to refer constitutional amendments, state statutes, and bond measures to the ballot. All legislatively referred measures require a simple majority vote during one legislative session to be placed on the ballot, and they do not require the governor’s signature to be referred to the ballot.

Measures referred to the ballot by the Oregon State Legislature or a commission totaled 437. Measures placed on the ballot by a successful citizen-initiated petition totaled 444. The approval rate for referred measures (58%) was nearly double the approval rate for initiated measures (35%).

Oregon ballot measures have addressed 81 unique topics with some addressing multiple topics in one measure. The top three topics were taxes, education, and state and local government finance. Some other notable topics included suffrage, the death penalty, fishing, and drug decriminalization:

• Between 1884 and 1912, Oregon voters decided on six measures related to suffrage for women. Suffrage was approved in 1912 after being defeated in 1884, 1900, 1906, 1908, and 1910.
• The original Oregon Constitution, adopted in 1857, included a provision prohibiting Black and multiracial persons from coming, residing, or being within Oregon, or holding real estate, making contracts, or maintaining suits in the state. The provision was moot with the ratification of the U.S. Constitution’s 14th Amendment in 1868. Voters rejected removing the provision from the Oregon Constitution in 1900 before approving repealing the language in 1926.
• Starting in 1908, there have been 19 citizen-initiated ballot measures related to fishing and fisheries. The first one, approved in June 1908, restricted salmon and sturgeon fishing in the Columbia River. The most recent one, defeated in 2012, would have prohibited non-tribal commercial fishers from using gillnets to catch salmon in the mainstem of the lower Columbia River.
• Voters decided on ballot measures in 1920 and 1922 to replace the state’s taxes with a single tax on the rental value of land. Both were defeated.
• In 1922, voters approved a ballot initiative to require children between eight and sixteen to attend a public school. The U.S. Supreme Court ruled that the initiative violated the U.S. Constitution on June 1, 1925. The unanimous decision held that, “The fundamental theory of liberty upon which all governments of this Union rest excludes any general power of the State to standardize its children by forcing them to accept instruction from public teachers only.”
• In 1936, voters rejected a ballot initiative to create a state-owned and operated Bank of Oregon.
• In 1994, Oregon became the first state to approve an initiative authorizing physician-assisted death.
• In 1996 and 2000, Oregonians rejected ballot measures related to the legislature’s power to review and approve or reject administrative rules.
• Also in 1996, voters approved a constitutional amendment to require a three-fifths (60%) vote in each legislative chamber to pass revenue-raising bills.
• In 2020, voters approved Measure 110, decriminalizing drugs in the state. The legislature re-criminalized the possession of certain drugs as misdemeanors in 2024.
• In 2024, voters defeated a ballot measure that would have established ranked-choice voting for federal and state executive offices. Oregon had decided on six ballot measures related to electoral systems before 2024, including top-two primaries in 2008 and 2014, and proportional representation-type systems in 1910, 1912, and 1914. Earlier, in 1908, voters approved a ballot initiative allowing for voting systems that enable a “direct or indirect expression of [a voter’s] first, second or additional choices.”

The average number of measures per decade was about 67, and the average percentage of measures approved per decade was 51.8%. The decade with the most ballot measures was the 1910s, which featured 137 ballot measures. Forty-six measures (33.58%) were approved, and 91 (66.42%) were defeated. The decade that had the highest approval rate was the 2020s, which has featured 13 measures—10 (76.92%) were approved, and three (23.08%) were defeated. The decade with the lowest approval rating was the 1930s. The decade featured 67 ballot measures—21 (31.34%) were approved and 46 (68.66%) were defeated.

There are eight different types of ballot measures in Oregon.  Legislatively referred constitutional amendments have appeared on the ballot the most number of times (359). Apart from the single bond issue that was approved in 1917, legislatively referred constitutional amendments had the highest approval rate at 59%. Initiated constitutional amendments had the lowest success rate at 33%. Legislatively referred measures have had better success at the ballot box than citizen-initiated measures. Legislatively referred measures were approved 58% of the time, as compared to 36% for ballot initiatives.

The inventory of Oregon statewide ballot measures is part of Ballotpedia’s Historical Ballot Measure Factbook, which will document nearly 200 years of direct democracy in the United States. This ongoing research effort will provide an unparalleled resource for researchers, reporters, and the voting public on how ballot measures have evolved, the issues they’ve covered, and the role they have played in our civic life.