Sarah Sparks writes in Edweek about a curriculum company that is suing a parent in Wake County, North Carolina, for criticizing its math program. The company says the parent is defaming its product. The parent’s lawyer says the company is attacking the parent’s First Amendment rights.

As the story notes, this is a SLAPP suit, a suit meant to silence public criticism. The last time I encountered this sort of thing was when a charter company filed a suit against a school board member in California for negative criticism. The ACLU came to her defense. It should defend this parent too, who is using his Constitutional right to disagree with a program adopted by his district.

A group of families in Wake County, N.C., have pushed for months to get the district to stop using a controversial new curriculum. Now the company behind the curriculum is suing one of the most vocal parents for defamation.

It’s a surprising move that some say could have broad implications for parent advocacy around curriculum and instruction. A win by the company “would certainly cast a shadow on the idea that parents have a right to participate in their own children’s education, to criticize schools for buying particular textbooks, to voice their concerns about instruction and curriculum,” said Tom Loveless, an education researcher formerly at the Brookings Institution, who is not involved in the case.

The Mathematics Vision Project, a nonprofit provider of open source math curricula, filed a complaint this summer against Blain Dillard, a parent in the Wake County public school system. MVP has accused Dillard, an outspoken opponent of the math program, of libel, slander, and “tortious interference with business relations.”

The company alleges that Dillard has launched “a crusade against MVP” through his online criticism of the curriculum and advocacy with school officials and employees.

In a written statement to Education Week, Jeffrey Hunt, Dillard’s lawyer, wrote that the lawsuit “has no legal merit.”

“It is alarming that a parent would be sued for defamation for expressing opinions and making truthful statements about his son’s high school math curriculum,” Hunt said. “The lawsuit appears to be an attempt to silence Mr. Dillard and other critics of MVP, and to chill their First Amendment rights to speak about MVP’s services.”

The district is entering its third year using the MVP curriculum, which received a favorable evaluation from the curriculum reviewer EdReports. The open source curriculum emphasizes problem-solving and collaboration—students learn by working through problems, and teachers are expected to act as facilitators.

For months now, parents have spoken out against lessons that they say are confusing and poorly structured, lodging complaints with the district and making statements at school board meetings. Parents said their children weren’t getting enough direct instruction and were encouraged to rely on their classmates for help. As a result, they said, students who used to get As and Bs were now getting Cs and Ds, which would have long-lasting effects on their grade point averages and college prospects.

Barbara Kuehl, an author and consultant at MVP, said that the organization’s materials encourage a variety of methods. “Our curriculum not only supports well-timed direct instruction, we advocate for it,” she said. Kuehl declined to comment on the lawsuit, citing pending litigation.

Pushback from parents over a new curriculum, and particularly a discovery-based program, is nothing new, said Loveless.

“There have been all kinds of programs that have been oriented around that philosophy, and they have been quite controversial,” Loveless said.

What is new? A curriculum provider suing parents over such complaints.