LOS ANGELES – White students in the Los Angeles school district are assigned better teachers on average than black and Latino students, due to the state’s tenure law and union-inspired layoff rules.

And the tenure law, which allows teachers to gain strong job security after slightly more than a year on the payroll, makes it difficult for schools to remove sub-par instructors.

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Those were the messages conveyed by several witnesses who testified last week in the high-stakes Vergara v. California trial in Los Angeles.

The lawsuit, filed on behalf of several California K-12 students, is challenging the state’s tenure law as well as teacher layoff policies based on seniority. It claims the laws and rules in question cost lower-income, minority students an equal chance at a quality education.

The state’s teachers unions are among those defending the status quo.

One witness in the trial, Harvard researcher Thomas Kane, recently published a report on how less effective teachers are disproportionately assigned to work with black and Latino students.

He testified on his findings last week.

According to LASchoolReport.com, Kane made “five overarching points: that’s it’s possible to implement measures of teacher effectiveness; that (the) L.A. Unified (district) has a higher ration of ineffective teachers than most school districts studied by other researchers; that a disproportionate number of ineffective teachers in L.A. Unified serve Latino and African-American students; that effective teachers have a causal effect on student achievement; and that teachers have long-term impacts not only on student achievement but also lifetime earnings.”

Kane, testifying for the plaintiffs, concluded that Latino students in the L.A. district are 68 percent more likely than white students to be taught by an instructor in the lowest five percent of effectiveness, and African-American students are 43 percent more likely.

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As a result, “deficits due to teacher quality for African-American students relative to white students amounts to 1.08 months of schooling lost every year,” said a media release from Students Matter, an organization that supports the lawsuit. “Latino students lose out on the equivalent of 1.55 months of schooling every year.”

This happens because the state’s tenure law and union-driven school policies allow teachers with more seniority to have first choice at prime teaching assignments in better schools, according to the plaintiffs. It’s also because the teacher layoff system is based on seniority rather than skill, and that it costs too much to fire an unqualified tenured teacher.

“Rather than assign (struggling minority students) more effective teachers in order to close the gap with white students, they’re assigned less effective teachers, which results in the gap being slightly wider the following year,” Kane testified, according to the newspaper report.

Kane’s study also identified similar trends in the New York City, Charlotte-Mecklenburg (North Carolina), Dallas, Denver, Memphis and Hillsborough County (Florida) school districts, the report said.

Other witnesses say teacher quality is crucial

Another witness for the plaintiffs, Kareem Weaver, an award-winning teacher and principal from the Oakland school district, testified that low-income minority students are particularly vulnerable to the failures of ineffective teachers.

“Low-income students of color are the most vulnerable population,” Weaver testified, at times breaking down in tears, according to the L.A. School Report. “It either props them up or blows them down,” he said of the children’s educational experience.

Another witness, Jonathon Moss, served as an instructor in the troubled Compton school district under the Teach for America program between 2008 and 2012. He testified how the “last in, first out” layoff policy ignores teacher quality at the expense of seniority.

Moss said he received four layoff notices during his time in the district, and “I know it had nothing to do with my performance. I know that I was an effective teacher and my colleagues were not.”

Moss described a “sense of mediocrity” prevalent among more senior teachers, and they knew it was okay because “their jobs were protected and they all had job security.”

Meanwhile, Mark Douglas, assistant superintendent for personnel services in the Fullerton, California school district, testified that the law allowing teachers to gain tenure protection after their first 16 months on the job is completely inadequate.

He said it takes far more time to determine if they will be effective teachers in the long run.

Douglas said that in his entire career, he’s only dealt with two teachers that he would have recommended for tenure after 16 months.

“It can be a crap shoot if that person can develop into the person you want,” Douglas testified.

But school districts are often stuck with ineffective teachers due to laws that guarantee tenured teachers a very thorough “due process” before they can be fired. Much of that process requires schools to pay heavy fees for legal representation in their effort to remove a teacher.

Douglas testified that would cost his district an estimated $2.5 million to dismiss what he described as “10 grossly ineffective teachers” currently on staff.

Douglas testified that he has spent as long as five years “in mostly unsuccessful efforts to improve their skills and create the voluminous paper trail he said is needed for successful dismissal hearings,” according to the report.

Douglas testified that he would prefer to dismiss the 10 teachers, whom he did not identify by name.

“The longer I have any of those teachers in the class, the more detrimental it is for instructional programs for kids,” Douglas said.