Micah Lasher, who heads the advocacy group StudentsFirstNY, said he is outraged about a recent blog from United Federation of Teachers Vice President Leo Casey.
The blog is titled "Blood Libel" and it asserts that lasher, Mayor Mike Bloomberg, and former CNN anchor Camplbell Brown -- among others -- slandered the UFT.
This all started last week when Brown criticized the teacher's union. In a newspaper commentary, she wrote that the union protects teachers accused of sexual misconduct in New York City.
That sparked a war of words on Twitter involving several groups, mainly the national teacher's union, the American Federation of Teachers, which claimed Brown was misrepresenting the facts.
Then came Casey's blog. In he wrote "the entirely false slander that we protect and defend sexual predators is, for us, the equivalent of blood libel."
You may remember Sarah Palin was criticized last year for using that same term, blood libel, to criticize the media after the Gabrielle Giffords shootings.
After Casey's post, the Anti-Defamation League called the use of the term blood libel "inappropriate and over the top."
Casey later responded, saying he regretted if it was in any disturbing to the ADL. But he said the criticism of the UFT was "so cynical in its use of children in an attempt to demonize us with falsehood, that it evoked that comparison for me."
Randi Weingarten, the head of the AFT, reacted on Twitter: "regrettable use of words - teachers & their union protect children; @leocasey was justifiable upset w/ charge that we don't."