Calling sex education an “important public right”, a California judge has created a potentially precedent-setting ruling that enforces state law barring abstinence-based teaching from schools.

“We believe it will have an important impact on other districts,” said Phyllida Burlingame, director of reproductive justice policy for the Northern California American Civil Liberties Union (ACLU). “Having this ruling will be a very powerful tool.”

Sex education must be “complete, medically accurate and free of bias” and cover more than abstinence, wrote California superior court judge Donald Black, in a ruling about instruction offered by the Clovis Unified school district in Central Valley, which serves about 40,000 students in an area with some of the highest teen pregnancy and STD rates in the state.

In 2003, California passed a progressive sex education law that took an all-or-nothing approach to a controversial subject. California schools are not required to teach sex education at all but it they do, they are mandated to adhere to an inclusive standard that embraces issues such as gender roles, HIV/Aids prevention, emergency contraception and sexual orientation and specifically prohibits abstinence-based approaches.

California currently has a bill in the legislature, AB 329, which would make sex education mandatory and clarify standards. However, under existing law districts are charged with creating their own programs and the content of those classes is not monitored by the state.

California has more than 1,000 school districts. According to Burlingame, more than 90% teach some form of sex education. But many schools do not comply with the law.

According to a 2011 study by the University of California at San Francisco (UCSF), more than a quarter of schools do not teach basics about HIV/Aids prevention and less than a third include teaching about sexual orientation.

Six percent of schools in the study admitted that they taught abstinence-only strategies, while 19% reported discussing birth control with an emphasis on the benefits of abstinence, another banned approach to the subject.

The Clovis suit was filed in 2012 by two parents – backed by the American Academy of Pediatrics, the Gay-Straight Alliance and the ACLU – who had tried unsuccessfully to have their school district update their teachings.

According to the suit, Clovis, a rural area in Fresno County, has for years been identified as a “hot spot” for sexually transmitted diseases and pregnancy in its young population. In 2010, teenage girls made up almost 35% of chlamydia cases and 30% of gonorrhea cases in Fresno County, despite accounting for only 8.3% of the population. In 2009, the area had the second-highest rate of reported chlamydia infections in California.

Still, the suit says the materials that Clovis teachers used in sex education included almost no information on birth control methods or condom use for preventing sexually transmitted diseases.

One tool used, the plaintiffs allege, was a video called Never Regret the Choice, which according to the suit encouraged children to “adopt the mantra ‘One man, one woman, one life’”.

In another video cited by the plaintiffs, a scene compared a woman who was not a virgin to a “dirty, used pair of shoes”, capable of transmitting foot fungus.

The suit also says some teachers taught that boys were likely to lose control once sexually aroused, and that girls were looking for love while boys only wanted sex.

“Those are not the messages we want to be giving young people and those are not the messages permitted by California law,” said Burlingame.

The district settled the suit in 2014 without admitting fault, but updated both its seventh- and ninth-grade sex education programs to include the required elements and eliminate some biased materials.

The ACLU and pro bono attorneys for the plaintiffs filed suit earlier this year, in order to recover fees. Judge Black’s April ruling – which focused solely on that issue but is the first legal ruling regarding the 2003 law – awarded them $467,000 from the district. Black, however, took the extra step of giving the overarching view of the importance of sex education.

“We thought it was fabulous that he took the time to sift through the issues and make a substantive ruling,” said Burlingame. “It was gratifying that the judge saw the importance of the case.”

Clovis Unified spokesperson Kelly Avants could not be reached for immediate comment. However, she told media outlets the issues “raised in plaintiff’s litigation were not accurate” and said the district was considering an appeal.