Teacher union power is awesomely arrogant.

In New York City, the American Federation of Teachers (AFT) is fighting efforts to restore order to schools. The school board wants teachers to supervise hallways, lunchrooms, and playgrounds because costly but ineffectual "paraprofessionals" don't command respect. But union leaders refuse to cooperate, even though their members work less than four hours a day.

In California, the National Education Association (NEA) is demanding control of school curricula. In Massachusetts, the NEA has fought teacher competency tests clear to the state supreme court. Elsewhere, the AFT and NEA are preventing the formation of union-free charter schools.

As private sector unionism has waned, the NEA and AFT have become the most powerful labor combination in America. They contribute millions to Democratic and Republican candidates for office. Teachers also constitute as many as a quarter of the delegates to the national Democratic conventions. In school board and school bond elections, teachers outvote citizens by large margins. In a bond referendum in Huntington Beach, California, 93 percent of the teachers voted, according to a Stanford study, though overall turnout was 19 percent; in nearby Santa Ana, 88 percent of the teachers voted, as compared to 23 percent of all registrants.

Yet for all this political influence, unions do not protect the earnings of the many good, hardworking teachers. In 1940, female teachers made better than 60 percent of that earned by average college-educated women; by 1990, they were earning 40 percent. Among males, salaries slipped from 52 to 33 percent of the college-educated average.

As pay has fallen, so has teacher quality. According to the Department of Labor, 50 percent of women entering teaching in the 1970s received high scores on an educational achievement test. Twenty years later, high-scoring female teachers constituted 10 percent of the total. For male teachers, the drop in high scorers was from 20 to 10 percent.

So what's gone wrong? Powerful unions should be fighting for wages that attract the best and the brightest. Part of the problem is insistence on uniform pay, whereby leaders resist attempts to reward teachers of special merit or pay more for those who have skills that are in short supply. More money is given only to those teachers with years of experience or added credentials. Because teacher effectiveness generally declines after five years, and teacher credentials have been proven meaningless, a disconnect exists between service rendered and compensation received. Thus, it makes little sense to pay employees more.

School boards and unions also take the line of least resistance by handing out more rights and less work rather than increasing teachers pay. Indeed, it was to keep wage demands down that the New York school board agreed to give hallway supervision to the paraprofessionals.

Moreover, ineffectual teachers make for loyal union members. And when ineffective teachers abound, more are needed: the ratio of pupils to teachers nationwide plunged from twenty-two to seventeen between 1970 and 1995. More teachers, more dues, more campaign contributions, more power, more rights--lower performance. No wonder lawmakers are beginning to talk accountability.

Paul E. Peterson is director of the Program on Education Policy and Governance, Harvard University; senior fellow, Hoover Institution; and member, Hoover's Koret Task Force on K-12 Education.