Oklahoma Gov. Mary Fallin (R) vetoed a bill on Friday that would have made it a felony for doctors to provide abortions, unless a woman's life is in danger or she has had a miscarriage that needs to be removed. There were no exceptions for rape, incest, or the woman's health.

"The bill is so ambiguous and so vague that doctors cannot be certain what medical circumstances would be considered 'necessary to preserve the life of the mother,'" Fallin said in a statement.

The bill defined abortion as "unprofessional conduct" for a physician, which meant that performing one could have been grounds for losing your medical license. Oklahoma's existing felony abortion law punishes non-physician care providers with up to three years in prison for performing an abortion. This bill, however, would have included physicians performing abortions.

So if you're a doctor, you would have risked both losing your medical license and going to jail if you provide abortions. In practical terms, that means the bill was a total ban on abortion.

Gov. Mary Fallin is anti-abortion. She didn't say in her statement that she vetoed the bill because it's unconstitutional; rather, she basically said that it's not a strong enough bill to be the one that directly challenges Roe v. Wade.

"The absence of any definition, analysis or medical standard renders this exception vague, indefinite and vulnerable to subjective interpretation and application," Fallin wrote in her veto message.

Fallin has recently signed a number of severe abortion restrictions in Oklahoma, including a 72-hour waiting period and a total ban on the safest, most common method of second-trimester abortion.

That second-trimester ban has been blocked by courts, since it's a pretty blatant violation of the Supreme Court's 1973 Roe v. Wade decision that legalized abortion until a fetus is viable. But it's a signal that in general, Fallin is willing to go to court to defend currently unconstitutional anti-abortion laws — even though the state is likely to lose, and waste money, in the end.

Some states keep trying to ban abortion even though it's unconstitutional

Oklahoma's attempt to ban abortion — classifying it as "unprofessional conduct" for doctors — is a new tactic that other states haven't tried before, said Elizabeth Nash, state issues manager at the Guttmacher Institute, an organization that studies and supports reproductive rights. Florida also tried to make it a felony to provide abortion earlier this year, but that bill died in committee.

A few states have actually passed and signed near or total abortion bans. Louisiana and Utah enacted abortion bans with limited exceptions in 1991. In recent years, North Dakota passed a ban on abortion after six weeks of pregnancy, Arkansas passed a 12-week ban, and Arizona passed an 18-week ban.

But all of these bans have been struck down by courts, and the Supreme Court refused to hear appeals. This is because Roe v. Wade is still the law of the land, even though it's been weakened by subsequent court decisions.

Later cases like Planned Parenthood v. Casey have made it easier for anti-abortion lawmakers to limit abortion in some ways. They can make women jump through hoops like 24-hour waiting periods, they can make doctors lie to women about the risks of abortion, and they can even pass regulations that are specifically designed to close abortion clinics (for now — the Supreme Court recently heard a major case on those).

But one still cannot simply pass blanket bans on abortion. The court has been very clear on that. Unless and until Roe v. Wade is overturned, passing laws like these will always to be a waste of time and money for states. The laws will be blocked immediately and overturned eventually, but not before a lengthy litigation process is complete.

Of course, overturning Roe v. Wade is exactly what some anti-abortion lawmakers are trying to do when they pass abortion bans. The hope is that these laws will be challenged all the way up to the Supreme Court, and that the Court will hear the case.

But so far, the Court has flatly refused to hear cases like these. With the current composition of the Court, they are just not a sound strategy to try to overturn Roe. (Twenty-week bans could be another story someday, since they've been blocked in some jurisdictions but not in others.)

That's why Fallin also said in her statement, correctly, that the "most direct path" to overturning Roe is the appointment of a conservative, pro-life Supreme Court justice.

Anti-abortion lawmakers might also be passing these bills as a statement of principle. But for now, that statement doesn't do much other than waste taxpayer money on court proceedings.

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