A great teacher can change the course of a kid's life.

But fewer students in New York will have the opportunity to be exposed to great teachers thanks to a policy supported by newly re-elected Mayor Bill de Blasio and his longtime backers in the United Federation of Teachers union.

Under this policy, the city's Department of Education is requiring schools to fill vacancies with men and women who already failed at teaching but are included on the city's Absent Teacher Reserve (ATR).

The Wall Street Journal writes this morning:

New York’s statistics show how awful many of these teachers are. Those in the absent teacher pool were deemed either “ineffective” or “unsatisfactory” at a rate 12 times higher than the city average. Roughly a third were yanked from the classroom because of a legal or disciplinary case. Teachers in the ATR can apply at any vacant position across New York City’s 1,700 public schools, so it’s worth wondering why 37% of ATR teachers haven’t managed to find any principal willing to give them a permanent job for four years or more.

Schools Chancellor Carmen Fariña has promised that ATR teachers won’t be foisted on any of the 86 struggling K-12s in Mayor Bill de Blasio’s Renewal School Program. That’s a tacit admission that these instructors pose a risk to student education. But ATR teachers can be forcibly placed at other troubled non-renewal schools, including East Fordham Academy for the Arts in the Bronx, where 98% of students lack basic math skills, and Brooklyn’s Lyon Community School, where just 8% of students achieve reading and writing proficiency.

As the editorial points out, at the same time the union is working to put people who already have washed out as teachers back in the classrooms, they are trying to make it harder to establish charter schools.

In an act of supreme irony, the union and its affiliates, which strive to keep lousy teachers in the classroom, are plaintiffs in a lawsuit challenging the certification standards of charter schools.