The ongoing debate about the controversial Healthy Kids Colorado Survey is becoming a story about a legal opinion pile-up.

The State Board of Education and the state health department each recently sought separate informal opinions on the topic from different assistant attorneys general. Now, the health department is seeking a formal opinion from the Colorado Attorney General’s office. That opinion, unlike the informal opinions, will be legally binding.

The issue at stake is what kind of parental consent is required before students take the biennial adolescent health survey. Currently, most districts use “passive consent,” which means students at select schools are given the survey unless parents sign a form opting them out.

But some critics of the survey, citing sensitive survey questions about sex, drugs and suicide, say advance written permission from parents–called active consent–should be required.

The original informal opinion presented to the State Board of Education in February stated that active consent is required for the survey under federal and state law, but at Thursday’s board meeting the attorney who wrote it said that the state law doesn’t apply to voluntary surveys. (Health department officials say the survey is completely voluntary, but some state board members say it may not be perceived that way.)

The second informal opinion provided to the health department late Thursday will not be publicly disclosed, said Mark Salley, director of communications for the Colorado Department of Public Health and Environment.

While it’s unclear if that second informal opinion aligned with the first, neither are legally binding. It will be the formal opinion now sought by the health department that will represent the final legal decision from the Attorney General’s office.

Salley said the formal opinion will be released publicly.