SAN FRANCISCO (AP) -- A federal court Tuesday struck down Arizona's ban on abortions after 20 weeks of pregnancy absent a medical emergency.
The 9th U.S. Circuit Court of Appeals said the law violated a woman's constitutionally protected right to terminate a pregnancy before a fetus is able to survive outside the womb. "Viability" of a fetus is generally considered to start at 24 weeks. Normal pregnancies run about 40 weeks.
Nine other states have enacted similar bans starting at 20 weeks or even earlier. Several of those bans had previously been placed on hold or struck down by other courts.
Judge Marsha Berzon, writing for the unanimous three-judge panel on the San Francisco-based court, said such bans before viability violate a long string of U.S. Supreme Court rulings starting with the seminal Roe v. Wade decision in 1973.
The judge wrote that "a woman has a constitutional right to choose to terminate her pregnancy before the fetus is viable."
Gov. Jan Brewer signed the ban into law in April 2012 after it was approved by the Republican-led Legislature. Supporters said the law was meant to protect the mother's health and prevent fetuses from feeling pain. U.S. District Judge James Teilborg ruled it was constitutional, partly because of those concerns, but the 9th Circuit blocked the ban from going into effect until it ruled.
Lawyers representing Arizona argued that the ban wasn't technically a law but rather a medical regulation because it allowed for doctors to perform abortions in medical emergencies. Berzon rejected that reasoning and deemed the legislation a law banning abortions before a fetus is viable.
"The challenged Arizona statute's medical emergency exception does not transform the law from a prohibition on abortion into a regulation of abortion procedure," Berzon wrote. "Allowing a physician to decide if abortion is medically necessary is not the same as allowing a woman to decide whether to carry her own pregnancy to term."
Berzon was joined by judges Mary Schroeder and Andrew Kleinfeld.
Cathi Herrod, the head of a Christian social conservative group that championed the 2012 legislation, said the ruling overlooks the state's interest in protecting maternal health," but that the outcome wasn't surprising because of the court's reputation as siding with politically liberal causes.
"We look forward to an appeal to the United States Supreme Court," said Herrod, president of the Phoenix-based Center for Arizona Policy. The group filed a legal brief in support of the Arizona law.
The 9th Circuit's ruling is binding only in the nine Western states under the court's jurisdiction, and Idaho is the only other state in the region with a similar ban. A federal judge earlier declared Idaho's ban unconstitutional.
Janet Creppe, a lawyer who argued against the ban in court for the Center for Reproductive Rights, said the ruling Tuesday affirmed a woman's right to an abortion before viability.
"These laws are all unconstitutional," she said. "This is not a close legal question at all. These laws are unconstitutional."
AP writer Paul Davenport contributed to this report from Phoenix.
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