The state teachers union is joining the city’s union in asking the court to toss out a lawsuit challenging teacher tenure laws in New York State.

The motion, filed by New York State United Teachers, claims that the plaintiffs do not have standing to bring their suit because only one parent claims to have a child in an ineffective teacher’s classroom. The brief also asserts that the state legislature, not the judicial system, is the appropriate place for decisions about teacher tenure and seniority rights to be made.

“The plaintiffs’ case rests on the fundamentally flawed and legally unsupportable proposition that because there may be some ineffective school teachers, all teachers should lose their basic employment safeguards,” the motion reads.

The city’s United Federation of Teachers made similar claims in a motion filed Tuesday.

The lawsuit, Davids v. New York, aims to replicate the outcome of a California case in which a judge ruled in June that the state’s job protections for teachers hurt low-income students. The lawsuit was formed after a judge combined two challenges filed in New York: one from parents organized by a group headed by former CNN anchor Campbell Brown and the other from parent activist Mona Davids.

The plaintiffs have until Dec. 5 to respond to the motion, according to the union, and arguments are scheduled for Jan. 14.

Read NYSUT’s full motion: