The debate over how to handle ineffective teachers resumed Thursday in a California appeals court, where three justices heard arguments from both sides of the Vergara v. California case.

The California Second District Court of Appeals will weigh a 2014 ruling by Los Angeles County Superior Court Judge Rolf M. Treu that struck down teacher tenure and dismissal rules across the state. These laws are meant to protect public school teachers' jobs but also prevent ineffective teachers from being dismissed.

During Thursday's hearing, representatives of the teachers' unions argued that the laws are not unconstitutional, as Treu had decided in 2014. They felt that unless the tenure and dismissal statutes led inevitably to poor education quality, they should not be struck down.

Implementation of the laws varies by district, the teachers' representatives said. Their attorney, Michael Rubin, argued that blame should fall on district administrators, not the laws themselves.

Attorney Theodore J. Boutrous, Jr., representing the education reformers, argued that the constitutionality of a law depends not on what it says but on its practical effects. The impact — that it costs hundreds of thousands of dollars to dismiss a teacher found to be ineffective — ensures, he said, that some students will have bad teachers.

Boutrous also suggested that the time it takes for a teacher to reach tenure in California should be lengthened, something the state legislature would have to enact.

Nine students brought the original lawsuit against the state in 2014. They argued that the state's laws regarding tenure and the process of dismissing ineffective teachers negatively impact students' education, especially that of low-income and minority students.

That lawsuit challenged three California statutes. One states that administrators have to either grant or deny tenure to teachers after a two-year period, which the plaintiffs say is too short a time to assess a teacher's performance.

Students also said that the teacher dismissal process is long and expensive, which makes it harder for schools to let ineffective teachers go. The plaintiffs at Thursday's hearing said it takes between $200,000 and $400,000 to fire a single teacher.

Students are also trying to do away with the "last-in, first-out" statute, which structures layoffs around seniority. Under this rule, teachers who have been at a school the longest are the last to be let go. Students want the dismissal process to place more weight on teachers' performance in the classroom.

According to these students, low-income schools get stuck with a disproportionately higher number of ineffective teachers, which denies their students an equal right to academic opportunities. Teachers on the opposing side of the case said that changing tenure laws would not help this problem because district administrators decide which teachers go to what schools.

One teacher, Gabriela Ibarra, said at Thursday's hearing that it is important for teachers to feel secure in their jobs so that they can speak up and advocate for their students without fearing punishment. Upholding the 2014 decision to strike down tenure laws would undermine that security, he said.

The appeals court must decide whether to overturn the original court ruling, which said that the laws are unconstitutional. However, both sides have said they intend to appeal if they lose this case, so it's likely that it will move on to the California Supreme Court. This district court appeal could be only an intermediary step in the legal process.

The three-judge panel has 90 days to reach a decision.

Reach Staff Reporter Sanika Bhargaw here.

Staff Reporter Rachel Cohrs contributed to this story.

Corrected Feb. 26, 6:15 pm Pacific Time — An earlier version of this story stated that in 2014 a judge found the state's tenure/dismissal laws "constitutional." It has been changed to correctly say that the laws were found unconstitutional.