WASHINGTON, D.C. – In a recent Detroit News editorial, Richard Berman puts the blame of America’s troubled education system exactly where it belongs: on the teachers unions.

Berman, executive director for the Center for Union Facts, explains how union work rules and contract clauses are hurting public schools by limiting principals’ staffing options and protecting poor or dangerous teachers.

Recent international test results show American students continue to slip farther behind their peers, and are now trailing students in Latvia, Slovakia, Estonia and Russia. Countries that spend less per student and have higher levels of immigration and poverty are also outperforming U.S. students, Berman wrote.

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“Education unions such as the American Federation of Teachers, which have had a stranglehold over public schools for decades, are deeply invested in the status quo. Union officials like the AFT’s Randi Weingarten spend millions of dollars every year lobbying against laws that would allow schools to fire poor performing teachers or oppose attempts to pay excellent teachers more without endless delays,” Berman wrote.

“Rather than streamline the system, unions have installed a cumbersome bureaucracy of work rules and regulations that ensure older teachers can keep their jobs over more talented younger teachers. Teacher union contracts regularly run longer than 100 pages, largely composed of work rules and other stifling regulations.”

Berman explained that America’s teachers unions spend heavily on political candidates, 95 percent of whom are Democrats, to buy influence and protect their interests in statehouses across the country. In 2011, the National Education Association – the country’s largest teachers union – spent $88 million, or 20 percent of its budget, on contributions, gifts and grants to left-wing causes, Berman wrote.

Berman illustrated the circle of death that has plagued the country’s public education system for years. The national teachers unions are certainly not the only element playing into America’s lackluster academic results, but they are the biggest factor.

Unions hold considerable sway over politics and school policy in virtually every state, but they have used their influence to lobby against charter schools and voucher programs that greatly improve student learning. They’ve also repeatedly lobbied against legislation that would make it easier to remove bad teachers and reward good ones.

The AFT and NEA have the power and influence to improve public schools, but have repeatedly demonstrated that’s not their focus. Teachers unions are focused solely on measures that would improve their revenue or boost their political influence, regardless of the effect on students.

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And, as Berman points out, that’s the problem.