school bus stock

Louisiana's tougher teacher tenure law has led to the exit of up to 1,700 public school teachers, according to a report issued Wednesday by Tulane University.

Educators close to retirement and those working in troubled public schools led the list of educators who fled after the 2012 law took effect, the study says.

"Our estimates suggest that the tenure reform is responsible for the exit of 1,500 to 1,700 teachers in the first two years after the removal of tenure protections, a loss of 3.0 to 3.5 percent of Louisiana's teacher workforce," the review says.

"The tenure reform created substantial churn in the Louisiana teacher workforce," the authors said.

The study was done by the Education Research Alliance for New Orleans, which is based at Tulane University.

The group's board includes officials of the state's two teacher unions, charter school advocates and others.

The report focused on a law that was part of then Gov. Bobby Jindal's push to overhaul public schools, whose scores have lagged behind students in most  states for generations.

Before the change five years ago, teachers routinely earned the job protection that tenure provides after a probationary period of 2-5 years.

The overhaul in Louisiana was part of a national trend.

The 2012 law made it difficult for starting teachers to earn tenure, and the new rules linked the job security of teachers to annual ratings based mostly on student achievement.

That set off alarm bells for some educators, and especially those with 25-30 years of experience.

In the two years after the law took effect, teacher exits rose 3.7 percentage points, according to the study.

The previous rate was just under 7 percent per year.

"The effects of removing tenure were greatest among teachers who were eligible for retirement with immediate, full pension benefits," the report says.

Top stories in Baton Rouge in your inbox

Twice daily we'll send you the day's biggest headlines. Sign up today.

Those teachers left the profession at a rate 2.6 percentage points higher than their counterparts with 10-19 years in the classroom.

Nathan Barrett, one of the authors of the report and associate director of the group, said veteran teachers especially see tenure as a big plus of the job.

"For some people it may be a matter of saying, 'You know what, this is not the teaching profession I got into so I am done,'" Barrett said.

Tenured teachers rated "ineffective" by the state  lose that job protection, and face an uphill battle to get  it back.

Other possible causes for the teacher exits, including the launch of the Common Core academic standards, were investigated but ruled out as likely causes for teachers quitting, according to the review.

Backers of the state's previous tenure policy said it offered teachers protection from arbitrary firings.

In another area, the report said after the tenure law took effect teachers leaving "F" rated public schools rose by 27 percent while the rate at "A" rated schools did not change.

"The tenure reform had a disproportionate impact on schools that typically face the greatest staffing challenges," the study says.

Teachers in poor-performing public schools typically work with lots of students from challenging backgrounds.

That boosts chances poor test scores will lead to a bad rating in annual teacher evaluations.

"You are not only taking away something from them they value," Barrett said. "But they also have the possibility of being exposed to more (job) risk."

The findings stemmed from a review of teacher employments records.

The authors studied teacher departures from 2006-11, before the law, to those from 2012 and 2013.

Teacher evaluation records, including those rated as ineffective, were not available for the first two years under the revamped tenure law.

Teacher ratings have largely been advisory for years during the move to tougher reading, writing and math standards sparked by Common Core.

Follow Will Sentell on Twitter, @WillSentell.