MSNBC host Rachel Maddow on Thursday night explained that some pro-life activists believe laws that criminalize virtually all abortions after 20 weeks of pregnancy are their best chance of overturning Roe v. Wade.

The Supreme Court's 1973's ruling in Roe v. Wade upheld a woman’s right to terminate her pregnancy until the fetus is viable outside the womb. But laws banning nearly all abortions after 20 weeks ignore viability. A fetus is typically considered "viable" after 28 weeks.

"These bans are totally unconstitutional," Maddow said. "Many of the people pushing for these bans admit they are unconstitutional. One anti-abortion group that wrote sort of model legislation for these things is on the record practically begging to be sued, begging for a court challenge, because they think if they get challenged on this, they might end up in court in a way that could have them overturning Roe v. Wade."

Although eight states have enacted laws that criminalize abortions after 20 weeks, they had not been challenged until Thursday, when the Center for Reproductive Rights and American Civil Liberties Union on filed suit against Arizona's partial abortion ban.

"The anti-abortion forces behind these bans now stand to get that big Supreme Court battle they have been looking for," Maddow said. "But if they lose, if the court's decide to uphold Roe v. Wade and strike down Arizona's ban on certain abortions, the seven states that are already enforcing bans might have to stop doing so."

Watch video, courtesy of MSNBC, below:

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