With the passage of Amendment 79 in November 2024, Colorado voters enshrined the right to abortion in the state constitution. The amendment solidifies the state’s status as one of the most liberal in the country on the issue.

It is a status that has been challenged over and over.

Since the 1973 Roe v. Wade Supreme Court ruling, Coloradans have voted on 10 abortion ballot measures – nearly one-sixth of all of the abortion-related ballot measures across the country. Despite public opinion consistently showing that Coloradans support abortion rights, eight of the 10 measures have sought to restrict access.

However, Colorado voters were not the first to have an abortion measure on the ballot. Voters in Washington, Michigan and North Dakota all voted on ballot measures in the 1970s to expand access to abortion. Only Washington passed the measure.

As part of my research examining how interest groups influence public policy, I have been tracking the activity of anti-abortion organizations, including the use of ballot measures. To understand the current climate in Colorado, it helps to understand how these ballot measures mirror debates within the larger conversation around abortion rights.

Coloradans’ views on abortion

Coloradans voted in 1910 to give themselves the right to vote on citizen-led initiatives or amendments. Currently, to get an initiative or amendment on the ballot, Coloradans need to gather signatures equal to 5% of the votes cast in the previous secretary of state election. Other states have higher signature thresholds, and this lower bar to entry helps explain why Colorado has so many ballot initiatives compared with other states.

Up until the 1960s, abortion across the country was largely restricted to therapeutic purposes – procedures done in the case of fetal anomalies or to protect the life of the mother.

In 1967 – six years before Roe v. Wade was decided and before any other state changed its laws – Colorado legislators loosened abortion restrictions. The new law allowed for abortions in the case of rape, incest, fetal anomalies and when the life or health of the mother is at risk.

Fast-forward to 2014, when polling from the Public Religion Research Institute showed that 64% of Coloradans believed abortion should be legal in all or most cases, compared with only 55% of all Americans.

Nearly a decade later, in 2023, 65% of Coloradans expressed that same support, while the national average rose to 64%. Residents of Wyoming, Utah, Nebraska and Oklahoma are all less supportive of legalized abortion compared with their neighbors in Colorado. Utah is the least supportive, with only 45% of residents supporting legalized abortion, while 56% of Oklahomans believe abortion should be legal in all or most cases.

Public funds for abortion

Even more controversial than legalizing abortion is the use of public funds to pay for them.

Since 1977, the Hyde Amendment has prevented federal money from funding abortions, except in cases of rape or incest or when the mother’s life is in danger.

Coloradans took up the issue of public funding of abortions in 1984. Amendment 3, a ballot measure to prohibit the use of state funds for abortions, narrowly passed with just over 50% of the vote. The measure applied a similar standard to state funds that the Hyde Amendment sets to federal funds.

Four years later, voters were asked whether the ban on public funding should be repealed. Only 40% of voters supported the repeal effort, yielding another early victory for anti-abortion activists.

In the November 2024 election, 62% of Coloradans approved Amendment 79, which repealed the prohibition on public funding and amended the state constitution to recognize the right to abortion.

Colorado is now one of 20 states that exceeds federal requirements and allows for state government funding of abortion. It joins nine other states to include the right to abortion or reproductive health in their constitution.

Failed attempts to restrict abortion access

In the background of this movement toward greater liberalization are decades of failed efforts by anti-abortion groups to push the state toward greater restrictions. While these groups have succeeded in getting measures on the ballot, they are frequently outspent by abortion rights groups.

In 1998, Coloradans voted on two abortion-related ballot measures. The first, Amendment 11, would have prohibited partial-birth abortions. The term, intended to evoke the image of an abortion just before birth, is also known as intact dilation and evacuation. These medical procedures are sometimes used for abortions during the second trimester, which account for less than 10% of all abortions, according to the Kaiser Family Foundation.

Voters narrowly rejected this measure; 51.5% opposed compared with 48.5% in support.

In the same 1998 election, voters supported requiring parental notification for minors seeking abortions. The vote came several years after the Supreme Court ruled in Planned Parenthood v. Casey that abortion restrictions in Pennsylvania were legal provided they did not place an “undue burden” on the patient. As a result of the ruling, states had more leeway to regulate abortion before fetal viability – an imprecise term that can mean anywhere between 20 and 25 weeks of pregnancy.

Ten years later, Colorado voters were the first to see fetal personhood on the ballot with Amendment 48. The initiative was sponsored by a law student, Kristi Burton, who created the organization Colorado for Equal Rights. While a grassroots effort, the amendment had the support of national anti-abortion groups such as the American Life League.

Voters rejected the constitutional amendment that would have defined personhood as beginning at the moment of fertilization. While the concept of fetal personhood was not new, policy around fetal personhood was picking up steam in the 2000s, especially after Congress passed the Unborn Victims of Violence Act in 2004.

In the 2008 Colorado personhood amendment campaign, abortion rights groups such as Planned Parenthood and Reproductive Freedom for All, formerly NARAL Pro-Choice America, spent more than US$1.75 million to defeat the amendment. In comparison, less than $500,000 was spent to support it.

The issue of fetal personhood did not go away. In 2010 and in 2014, Colorado voters were presented with constitutional amendments to define personhood – but the measures attracted support from only 29.5% and 35% of voters. Both years, abortion rights groups far outspent those supporting the personhood amendments.

Another defeated measure, Proposition 115, would have prohibited abortion after 22 weeks of pregnancy. Only 41% of the voters supported the measure.

Colorado in a post-Roe America

Colorado’s abortion policy is now more liberal than all of its neighbors, with the possible exception of New Mexico, which places no restrictions on when abortions may occur but does not explicitly protect the right to abortion.

Oklahoma prohibits abortion except to save the life of the pregnant person. Utah limits abortion after 18 weeks, and Kansas restricts abortion after 22 weeks.

In November 2024, Nebraska voters rejected one constitutional amendment that would have protected the right to abortion and supported a measure to prohibit abortion after 12 weeks. It was the first time since the Dobbs v. Jackson Women’s Health Organization decision, which overturned Roe v. Wade, that voters were presented with two competing measures.

Nearly 1 in 5 patients travel outside their home state to receive abortions, according to the Guttmacher Institute. Colorado has become a destination for patients from neighboring states seeking care.

This is likely to place a strain on the state’s health care system – and could encourage anti-abortion activists in the state to try their luck again on the ballot.

Anne Whitesell is a 2024-2025 PRRI Public Fellow.