Gov. Mark Dayton said last week that he plans to veto a GOP-sponsored proposal that would replace the state's seniority-only layoff system for teachers. The governor should reconsider. Making tenure one of several criteria -- but not the only one -- in determining layoffs would better serve the interests of students, families and effective teachers.

This week a legislative conference committee approved the tenure law change, and the full House and Senate are expected to accept it as well. The governor will then have three days to either reject the bill or sign it into law. Those hungry for smart, timely reform of Minnesota's schools should prepare to be disappointed.

Under Minnesota's current "last in, first out" (LIFO) teacher tenure laws, schools must lay off teachers based only on seniority unless school boards and teachers unions negotiate their own layoff policy. The proposed bill would require districts to consider teacher performance, licensure and seniority when making staff cuts.

Minnesota Department of Education Commissioner Brenda Cassellius, the statewide public teachers union and many Democrats have opposed the measure. One of their constant refrains is that the bill is premature because a statewide teacher evaluation system approved in the previous legislative session is still being developed.

That's an insultingly weak argument. The tenure law change would go into effect in the 2016-17 school year, allowing plenty of time for the new evaluation system to be in place.

Dayton called the tenure bill "more of a political ploy than a serious policy attempt." He added that it was among several Republican initiatives introduced this session aimed at undermining teachers, public schools and unions.

While there's no doubt the GOP playbook this session has included several misguided attacks on unions, Dayton is playing politics himself by lumping sensible LIFO reform into that category. His position is in lockstep with Education Minnesota, the state's powerful teachers union.

Meanwhile, there's significant public support for ending seniority-only layoffs. Nearly 80 percent of Minnesotans agree that teacher effectiveness should be considered when making layoff and firing decisions, according to a recent survey by the Minnesota Campaign for Achievement Now (MinnCAN).

Coalitions of local business, parent, community and minority groups support saving the best teachers from layoffs. The national StudentsFirst education reform group, for example, has distributed fliers to Minnesota homes, encouraging citizens to contact the governor in support for the measure.

As StudentsFirst-Minnesota points out, LIFO has several negative affects on students. Studies indicate that seniority-only layoffs force districts to dismiss some of their most effective educators. LIFO policies also increase the number of teachers who are let go in budget-cutting layoffs because less-senior teachers have lower salaries.

Seniority-only based layoffs also do more damage in high-needs schools, which tend to have less-senior staffs teaching more struggling students.

If Dayton follows through on his threat to veto this sensible change in the state's teacher tenure law, he'll miss an important opportunity to help improve education. Minnesota students deserve to have the best teachers in their classrooms.

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