The U.S. Supreme Court handed down a split decision Tuesday in a key labor case. 

At issue was Friedrichs v. California Teachers Association, a case focused on union “fair share” fees. The U.S. Supreme Court’s 4-4 decision in the case leaves in place a lower court ruling, which upheld the fees. 

The nation’s high court was left with eight members after last month’s death of conservative-leaning Justice Antonin Scalia.

A group of 10 nonunion public school teachers in California who object to paying the fair share or “agency” fees to their local union brought the case. The plaintiffs — represented by the the Center for Individual Rights (CIR), a conservative public interest law firm — argued that the mandatory fees, which support costs associated with collective bargaining, violate their First Amendment rights.

Plaintiffs wanted the Supreme Court to overturn its decision in the Abood v. Detroit Board of Education case from 1977, which allowed unions to require those they represent, but who are nonunion members, to pay fees to cover bargaining costs.

Illinois Republican Gov. Bruce Rauner filed an amicus curiae, or “friend of the court,” brief in support of the plaintiffs. In Illinois, Rauner is going after mandatory nonmember union fees and wants to limit collective bargaining in the public sector. He has also pushed for right-to-work zones in Illinois.

California Teachers Association President Eric Heins issued a statement on today’s 4-4 Supreme Court decision. 

“Collective bargaining rights allow educators, like me, to speak up for their students on important issues such as class sizes and high-stakes standardized tests,” he said. “Today’s ruling by the Supreme Court reaffirms that it is in the best interest of our students and our communities for educators to have a strong voice on the job.”

The National Education Association, a union respondent in the case, also applauded the outcome of the ruling.

“The U.S. Supreme Court today rejected a political ploy to silence public employees like teachers, school bus drivers, cafeteria workers, higher education faculty and other educators to work together to shape their profession,” NEA President Lily Eskelsen Garcia said in a statement. “In Friedrichs, the court saw through the political attacks on the workplace rights of teachers, educators and other public employees. This decision recognizes that stripping public employees of their voices in the workplace is not what our country needs.”