It seems to me there is a terrible amount of confusion over the concept of tenure. I find it impossible to believe that any judge could claim the tenure system to be unconstitutional, as a California judge apparently recently ruled. As I understand it (or perhaps misunderstand it) the concept of tenure did not arise because it was to provide permanence of employment to any and every professor/teacher no matter how bad they may be at their chosen profession. There is nothing in the tenure system that prohibits bad, especially really bad, teachers from being fired. Tenure has basically nothing to do with permanence of employment.
Tenure exists primarily for one major reason, and one major reason only: to insure that no one can be fired for expressing and teaching ideas that may not be in the mainstream of opinion. In short, to guarantee the First Amendment right to free speech. This prohibits teachers from being fired for political reasons at the whim of administrations that may not approve of, say, socialist or communistic ideas, or other ideas that may not be in the current mainstream of current belief. Galileo, for example, could not have been fired for teaching that the earth revolved around the sun, or Darwin could not have been fired to suggesting and teaching the theory of evolution.
If this is true, and I believe it is, there is nothing in the tenure system that prevents a bad professor/teacher from being fired if their performance is found to be consistently bad or inappropriate. Tenure should not be automatically awarded to a bad teacher simply because that individual managed to last for two or more years. And it should not be particularly difficult to uncover the reasons why any individual teacher is being fired.
If, in fact, the tenure situation in California is such that truly bad teachers are being automatically retained because of two or more years of no matter how lousy performance they have completed, and if it is also true that these terrible teachers are being systematically assigned to the worst (usually minority) schools, this is a terribly harmful and unjustifiable procedure. But this is not a result of the tenure system, it is a result of the egregious ABUSE of the system.
I believe that the tenure system has in fact been seriously abused. Some schools, even probably many schools, have confused the idea of tenure with the idea of permanence of employment simply because of survival for a relatively short time. Tenured faculty can and should be fired if they are found to be incompetent, irresponsible, criminal, mentally unbalanced, or otherwise offensive, but they should not be fired for espousing views that are out of the mainstream of contemporary acceptability. In any given case the reasons for firing a teacher should be subjected to a careful examination by an independent examining body and determined on the evidence submitted for the action. Tenure should not exempt anyone from the possibility of losing their job due to incompetence, irresponsibility, criminality, or consistently poor performance. On the other hand new or unpopular ideas should not be muzzled by those fearful of change or obviously biased in their beliefs.
Where would we be without Galileo, Darwin, Freud, Einstein, and the other creative giants of the past had they been untenured (actually they were untenured and forced to pay a price for their ideas, which only makes the necessity of tenure more obvious).
The whole purpose of annual reviews is to keep you abreast of whether or not you are fulfilling the requirements of tenure.