The Oklahoma Supreme Court has thrown out another state law that would put new restrictions on abortion providers.

In a unanimous opinion handed down Tuesday, all nine justices agreed that the statute adopted by the Legislature last year "contains different and unrelated purposes" in violation of the Oklahoma constitution's requirement that legislation cover a single subject.

The law encompasses four abortion-related topics: minors and parental consent; tissue preservation; inspection of clinics; and legal liability for abortion providers.

The New York-based Center for Reproductive Rights challenged the law and the state's highest court subsequently blocked it from going into effect. The center sued on behalf of Dr. Larry Burns of Norman, who performs nearly half of Oklahoma's abortions.