The ruling earlier this week by a California state court judge eviscerating the teacher tenure law in that state is already being hailed by some as a step toward improving the quality of public education there and, perhaps, in other parts of the country, too.

In the case, Vergara vs. California, brought on behalf of nine public school students in Los Angeles, the judge scathingly ruled that teacher tenure, a union-backed system that gives job security to veteran teachers, violates the state constitutional right to education and that it has an unfairly disproportionate negative impact on poor and minority children by saddling them with ineffective teachers.

The decision was praised by many, especially those who disdain unions and their members, like the Silicon Valley magnate who financed the case. But those who are truly concerned about rights of students and employees ought to be wary of that case becoming a precedent for dismantling teacher tenure in Minnesota.

There are some significant differences between teacher tenure here and the system that the judge deemed "shocks the conscience" in California. For one thing, tenure takes up to three years or more to attain in Minnesota, compared with 18 months in California, providing a better vantage to assess a teacher's qualifications. Unlike California, where tenured teachers are nearly impervious to removal, Minnesota law provides a framework for removing a tenured teacher upon a showing of "inefficiency" as well as for misconduct or other misbehavior.

But apart from these disparities, there are other reasons that Minnesota should be reluctant to embrace the assault on teacher tenure. Teaching is a low-paying job that offers few benefits to its practitioners. Providing them with job security after a reasonable time of work encourages more aspiring educators to join the ranks of teachers. Without tenure, there would be fewer teachers, resulting in a diminution in the quality of public education.

Moreover, the judge's rationale for eliminating tenure bodes badly for other professions. Many public-sector employees — including those in police, fire and other protective services — have a seniority system that operates much like tenure for teachers. While it does not assure them of continued employment, it furnishes job security to those who have been there longer and, in many cases, would be vulnerable to being let go because of their age in order to hire younger, less-costly employees. The seniority system, like tenure, is a barrier against facilitating cheap labor, which drives down wages for everyone else.

In his blistering decision, the judge ripped into the way tenure creates "lifetime" jobs for teachers, regardless of competence or fitness. As a state court judge, he is subject to job renewal from time to time. But his colleagues on the federal bench are guaranteed lifetime positions, subject only to the rarity of impeachment. If tenure for teachers is a bad idea, it is even more perverse to have lifetime appointment for the federal judiciary, regardless of competence — or senility — as sanctified in the U.S. Constitution.

No one, even the unions that support tenure, wants to see ineffective teachers or bad or slothful ones perpetuated. The tenure system may need reform, as the Minnesota Legislature has done occasionally, but the California ruling is a bad lesson that should not be emulated here.

Marshall H. Tanick, of Minneapolis, is an employment and education law attorney.