Missouri legislators criminalized a type of late-term abortion today after overriding the veto of Gov. Mel Carnahan (D).

Bans on "partial-birth" abortion have been struck down in courts across the nation, but Missouri's Infant's Protection Act goes farther than most. It creates a felony crime specifically called "infanticide" that subjects anyone who causes "the death of a living infant . . . by an overt act performed when the infant is partially born or born" to charges equivalent to murder.

The law's only exception is when the life of the pregnant woman or another fetus is at risk.

Democratic Sen. Ted House said Missouri's approach was different from other states' because the ban on late-term abortions is written into Missouri's criminal code.

"We draw the line at infanticide," House said. "This statute has never been ruled on."

Carnahan has vehemently opposed the measure, saying it could be interpreted as a legal defense for violence against abortion providers and could end up outlawing more abortion procedures than the one lawmakers meant to target.

"This bill is far more extreme than its proponents claim," Carnahan said.

There is no record of the procedure ever having been performed in the state. But Planned Parenthood, Missouri's largest abortion provider, said it will suspend all abortions because of questions about their legality under the new law.

Planned Parenthood affiliates in Kansas City and St. Louis said they would ask federal courts on Friday to put the law on hold while they challenge it.

Critics and supporters predicted the Missouri law eventually would reach the Supreme Court. Some critics have said it could be used to challenge the 1973 Roe v. Wade decision that legalized abortion.

The Missouri Senate's vote today was 27 to 7; the House vote Wednesday was 127 to 34.