trigger laws
Trigger laws are laws designed to take effect after a major shift in controlling law occurs. Legislatures will write laws with the intention that those laws come into effect after a shift in the law allows them to be legally enforced. Typically, trigger laws are created at the state or local level and rely on a shift in controlling law, either through a change in federal statute or case law, like a major U.S. Supreme Court decision. For example, in anticipation of Dobbs v. Jackson Women's Health Organization, 597 U.S. 215 (2022), many states prepared trigger laws banning abortions that, under the then-existing Roe v. Wade, 410 U.S. 113 (1973) precedent, would have been unconstitutional. These laws went into effect immediately upon the release of the Dobbs decision, which overturned the precedent in Roe.
Trigger laws may also rely on policy change. For example, under the Patient Protection and Affordable Care Act of 2010 (ACA), the federal government is mandated to fund a predetermined percentage of Medicaid expansion. Several states instituted trigger provisions to cancel their Medicaid expansion funding should the federal government’s contribution requirements fall below that percentage. These laws went into effect as federal funding for the program subsequently decreased and fell below that initially set requirement.
[Last reviewed in May of 2026 by the Wex Definitions Team]
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