Wichita ? A federal judge ruled Monday that doctors, nurses and other health care professionals in Kansas cannot be forced to report instances of underage sex to authorities.

U.S. District Judge J. Thomas Marten issued a preliminary injunction barring Kansas officials from enforcing provisions in a state law that, according to Atty. Gen. Phill Kline, requires health care professionals to report underage sexual activity.

Marten wrote in his ruling the court was hesitant to sanction Kline’s “monumental change in policy” given its imposition on the privacy rights of minors.

“The court is convinced even a limited breach of confidentiality concerning such unique and intimate information could have large implications for the well-being of minors,” Marten wrote.

Kline said in a statement that he would seek an immediate appeal.

“The state has a strong interest in protecting children from abuse,” Kline said. “Child predators desire two things: access to children and privacy.”

In his ruling, Marten said that Kline’s opinion last year actually clarified the reporting statute and provided fair notice of when reporting is required.

“The court appropriately upheld the state mandatory reporting statute against plaintiffs’ challenge that it was unconstitutionally vague, and found that my 2003 opinion clarified the law,” Kline said.

However, Kline said that the court in issuing the injunction concluded that minors have a right to informational privacy — a decision that has not previously been reached by any other court in this circuit.

Sex involving someone under 16 is illegal in Kansas, even if it involves willing same-age partners. Last July, Kline issued an opinion on the state’s 1982 reporting statue, which he said required doctors, nurses, psychiatrists, social workers and others to report such illegal underage sex to law enforcement officials or the Kansas Department of Social and Rehabilitation Services.

Kline said such reporting was required by the law because such sex inherently involves abuse of a child. His opinion differed from one issued in 1992 by one of his predecessors, Robert Stephan, who said health care professionals have some discretion in whether they report sexual activity.

“The court is also struck by the magnitude of the change in policies outlined in the 2003 advisory opinion,” Marten wrote. “It is persuasive that the parties operated under the 1992 advisory opinion for a substantial period of time without discernible problems.”

The Center for Reproductive Rights, a New York advocacy group that filed the lawsuit last year, contends that forced reporting of even consensual sex discourages youths from seeking counseling or medical treatment.

“The significance of the ruling is that it means adolescents in Kansas can access confidential health care services,” said Bonnie Scott Jones, attorney for the Center for Reproductive Rights. “Reporting all teen sexual activity violates adolescents’ privacy rights. This ‘kiss and tell’ law does nothing to address real abuse of children.”

By age 16, about 30 percent of adolescents in the United States have engaged in sexual intercourse, most of it with peers, according to the lawsuit.

She called the Kansas law probably the most extreme in the country because it makes virtually all sexual activity by juveniles illegal, regardless of difference in age between partners and whether it is consensual.

Fewer than 1 percent of abused children self-report their own abuse, Kline said.

“I don’t see this as having anything to do with the attorney general opinion other than the attorney general opinion further clarifying the reporting statute in the mind of the judge,” said Eric Rucker, a senior deputy attorney general. “He didn’t strike down the AG opinion.”

The plaintiffs contended in their lawsuit that an investigation by social services generally gives notice to parents concerning the type of health care sought by the minor, including contraception and abortion. The argued that the mandatory reporting would impose substantial obstacles on adolescents seeking abortions.