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Vergara trial expert witness: ineffective teachers hurt students

Mark Harris | January 29, 2014



Raj Chetty, Harvard Economist

Raj Chetty, Harvard Economist

And so begins the battle of the expert titans.

In the landmark lawsuit, Vergara vs. California, the winner may ultimately be the side that had the more persuasive expert witnesses.

The first came to the stand today as lawyers for the nine students bringing the suit called Harvard professor Raj Chetty, a renowned expert in public policy economics whose judgements, he said, are relied upon by President Obama and Congress.

The case hinges on whether five statutes written into the state constitution protect ineffective teachers, thereby violating students’ constitutionally protected right to a quality education. The defendants — the California Teachers Association (CTA), the California Federation of Teachers (CFT) and the state — say they do not.

Armed with mounds of empirical data, documents and exhibits, the 34-year-old professor offered testimony supporting the plaintiffs’ key points: that teacher quality has a direct impact on students’ achievements and that the current dismissal and seniority statutes have disparate impact on minority and low-income students.

Drawing a few laughs from the courtroom, Chetty testified that he believes elementary teachers are, in fact, even more consequential than college professors. But under questioning from Ted Boutrous, a lawyer for the plaintiffs, he quickly got down to business, explaining results from his research, notably that teacher effectiveness can be measured, and long term gains for students are the direct result of effective teachers.

A key part of the plaintiffs’ case is that California tenure laws do not provide adequate time to determine a teacher’s effectiveness. Chetty agreed that 16 months is insufficient and is ultimately detrimental to students. He went on to testify that teacher layoffs based on seniority also pose harmful effects on students, and are even more pronounced with minority and low income students.

Using a series of graphs from his own research, he showed the court how he determined that students test scores improve with an effective teacher and suffer with an ineffective teacher.

He explained that his research also takes into account external forces that might influence academic success, but nothing, he said, predicts “future success” more than effective teachers.

They’re even more important than smaller class size, he said, shooting a hole in a favorite theory of teacher unions. Given a choice between a smaller class size or one quality teacher, “I’d rather choose the higher quality teacher,” he said.

Earlier in the day, John Deasy, Superintendent of LA Unified, wrapped up his testimony after three days on the witness stand. Looking tired and sometimes exasperated, he appeared as if he were being held after class for detention.

After some confusion over exhibits, Supervising Deputy Attorney General Susan Carson continued with her cross examination and questioned the witness about the dismissal and seniority laws the plaintiffs are challenging.

Attacking a key component of the plaintiff’s case, the defense tried tirelessly to show that the laws don’t prevent LA Unified from assigning more experienced teachers to high poverty areas when vacancies are available.

But Deasy testified that the reduction-in-force statute does affect the assignment of teachers. When asked if a grossly ineffective teacher was ever intentionally assigned to a high poverty school, the educator stated “Regrettably, yes.”

The morning session was cut short. Superior Court Judge Rolf M. Treu called for a recess after the court reporter had to stop. And, it wasn’t a question of tired fingers. She lost her internet connection.

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