Missouri  Gov. Jay Nixon  (The Washington Post)

The fighting over the Common Core initiative continues: A Missouri judge said the state’s membership in a federally funded testing consortium charged with creating an assessment aligned with the Common Core standards is illegal. And what’s more, he ruled that the state should stop paying fees to the group, the Smarter Balanced Assessment Consortium.

The ruling, which is expected to be appealed and well may not stand, is the newest salvo in what is an increasingly heated debate over Common Core State standards. The Associated Press reported that the state had budgeted about $4.3 million to pay dues to the SBAC this fiscal year.

The tactic of going to court to stop membership in a Core consortium could spread to other states by Core critics.

SBAC is one of two multi-state consortia funded with some $360 million from the U.S. Department of Education to design new accountability tests aligned to the Core standards. In 2010, SBAC had more than 30 members; today there are no more than 20. The other consortium is the PARCC, or Partnership for the Assessment of Readiness for College and Careers. PARCC has experienced its own troubles; it had 26 states in 2010 but now fewer than a dozen states and the District of Columbia are taking the PARCC test this year.

The lawsuit against Gov. Jay Nixon, a Democrat, and other officials was brought by plaintiffs Gretchen Logue and Anne Gassel of the Missouri Coalition Against Common Core along with a former GOP gubernatorial candidate, Fred N. Sauer. Cole County Circuit Court Judge Daniel Green ruled that SBAC itself is

“an unlawful interstate compact to which the U.S. Congress has never consented, whose existence and operation violate the Compact Clause of the U.S. Constitution, Article I, § 10, cl. 3, as well as numerous federal statutes; and that Missouri’s participation in the Smarter Balanced Assessment Consortium as a member is unlawful under state and federal law.”

Here’s the ruling: