by Christine Vestal, Stateline.org

The U.S. Supreme Court may loom largest in the legal history of abortion in the United States, but from the 1800s to today state capitols have been the crucibles of America’s evolving policies toward a woman’s right to end a pregnancy.

The trendsetter was Massachusetts, which in the mid-1800s became the first state to outlaw abortion, a practice legal in colonial times. Continuing that trend, South Dakota this year passed a strict new ban on abortion geared to set up a direct challenge to the high court’s 1973 Roe v. Wade ruling legalizing abortion.

In the 33 years since the landmark Roe decision, states have taken a variety of approaches to limiting access to abortion, from requiring minors to seek a parent’s consent for an abortion to regulating the size of doorways in clinics that perform the procedure. Four states – Illinois, Kentucky, Louisiana and South Dakota – have so-called trigger laws waiting on the books to make abortion illegal as soon as federal policy permits and three others have policy statements opposing abortion.

In contrast, 13 states help ensure a woman’s access to abortion by prohibiting most forms of protest at abortion clinics. Seven states have passed laws ensuring the legality of abortion whether Roe v. Wade stands or falls and California and nine others have constitutional language interpreted by courts as protecting a woman’s right to end her pregnancy.

Any Supreme Court ruling overturning or weakening Roe v. Wade would trigger an epic battle between “pro-life” and “pro-choice” forces that likely would be fought in state capitols – and perhaps also in Congress.