OKLAHOMA CITY — An Oklahoma judge has temporarily blocked a state law that would keep minors from obtaining the Plan B contraceptive pill without a prescription, on the grounds that lawmakers may have violated a constitutional technicality in writing the bill.

District Judge Lisa Davis on Aug. 19 granted a request for a temporary restraining order on the law, which requires women under 17 to have a prescription to obtain the Plan B One-Step pill and generic emergency contraceptives. The law requires women 17 and older to show identification to a pharmacist to acquire the drugs.

Attorney General Scott Pruitt’s office voiced disappointment in the judge’s decision.

“The law simply keeps requirements the same as they have been for more than a decade, requiring those under age 17 to have a prescription to buy Plan B emergency contraceptives,” said Diane Clay, spokeswoman for the attorney general.

The Oklahoma Legislature passed the law in reaction to the federal government’s decision in June to allow unrestricted over-the-counter sales for emergency contraception. The state law would have taken effect Aug. 22.

Davis said she was concerned about whether the law met state requirements governing what laws can be passed. The morning-after pill provisions had been added to a bill about regulations for health-insurance benefit forms.

Opponents of the restrictions, including attorney David Brown of the New York-based Center for Reproductive Rights (CRR), argued that the addition of the restrictions to H.B. 2226 violated the state Constitution’s requirement that proposed laws must cover only one issue.

The CRR also charged that the law discriminates against women.

However, Solicitor General Patrick Wyrick noted that the law preserves the status quo before the federal action. He denied that the provision was “log-rolled” into passage.

“It was just a matter of legislative necessity,” he said.

The law’s opponents are seeking a permanent injunction against the law.

Federal approval of broad access to the drug followed a New York federal judge’s April order that the morning-after pill must be made available without a prescription to women of any age.

Deirdre McQuade, spokeswoman for the U.S. bishops’ Secretariat for Pro Life Activities, warned in April that broad access to the drug makes young girls more vulnerable to sexual predators and to harmful side effects of the medication.

McQuade said that allowing broad access to the drug “undermines parents’ ability to protect their daughters.”