By JAMES MacPHERSON
BISMARCK, N.D. (AP) -- Republican Gov. Jack Dalrymple signed into law a measure that outlaws abortions after 20 weeks of pregnancy based on the disputed premise that at that point a fetus can feel pain.
The law signed Tuesday is the latest among a raft of measures passed in North Dakota this session that are meant to challenge the U.S. Supreme Court's 1973 Roe v. Wade ruling that legalized abortion up until viability, usually at 22 to 24 weeks.
Abortion-rights advocates have called the laws blatantly unconstitutional and have promised a long legal fight that they say the state can't win.
Dalrymple last month signed a law that bans abortion as early as six weeks, or when a fetal heartbeat is detected, making North Dakota the most restrictive state in the nation in which to get the procedure.
Dalrymple also signed into law last month other measures that make the state the first to ban abortions based on genetic defects such as Down syndrome and require a doctor who performs abortions to be a physician with hospital-admitting privileges. The measures also ban abortion based on genetic selection.
Abortion-rights activists say the signed measures, which take effect Aug. 1, are aimed at closing North Dakota's sole abortion clinic, the Red River Women's Clinic in downtown Fargo.
At least 10 states have passed bills banning abortions after 20 weeks of pregnancy on the premise that a fetus can feel pain at that stage, but research is split on the theory.
North Dakota lawmakers also moved last month to seek a referendum measure defining life as starting at conception, essentially banning abortion in the state. The measure is likely to come before voters in November 2014.
The Center for Reproductive Rights has said it is committed to challenging the fetal heartbeat bill on behalf of the clinic.
The New York-based group is representing the clinic for free in a trail that started Tuesday over a 2011 law banning the widely accepted use of a medication that induces abortion. A judge has temporarily blocked enforcement of that law.