SF teachers union official on leave after sting video released

Project Veritas co-founder James O'Keefe, left, and Stan Dai leave the St. Bernard Parish jail a taxi cab in Chalmette, La., Tuesday, Jan. 26, 2010. O'Keefe, a conservative activist who posed as a pimp to target the community-organizing group ACORN, was one of four people arrested by the FBI and accused of trying to interfere with phones at Sen. Mary Landrieu's office in New Orleans. On Tuesday, Project Veritas released an undercover video in which a San Francisco teachers union staffer appears to admit to once assaulting a student and covering it up. less Project Veritas co-founder James O'Keefe, left, and Stan Dai leave the St. Bernard Parish jail a taxi cab in Chalmette, La., Tuesday, Jan. 26, 2010. O'Keefe, a conservative activist who posed as a pimp to ... more Photo: Patrick Semansky, ASSOCIATED PRESS Photo: Patrick Semansky, ASSOCIATED PRESS Image 1 of / 4 Caption Close SF teachers union official on leave after sting video released 1 / 4 Back to Gallery

A San Francisco teachers union official has been placed on administrative leave following the release of an undercover video Tuesday in which he appears to admit he assaulted a student and covered it up.

San Francisco school officials and labor leaders are investigating the contents of the video released Tuesday by Project Veritas, a nonprofit known for legally and ethically questionable undercover video stings involving labor unions, the community-organizing group ACORN and National Public Radio.

The edited footage released Tuesday includes separate conversations in 2015 between Antonio Mankini, treasurer and field representative for the United Educators of San Francisco, and two Project Veritas staffers, one posing as a friend of a district teacher who hit a child and the other as the teacher himself.

Mankini appears to admit he once “clotheslined” a student, but made it look like an accident.

“And that one still bothered me,” Mankini appears to say in the video. “That one, yeah, because I crossed the line. I know, I mean, I made it look like an accident and all the witnesses would have said, ‘No, he ran into my arm.’”

He notes that hitting a child with a fist is “pretty serious stuff.” But he also appears to offer advice to the purported teacher.

“Were there any witnesses?” Mankini asks. “Just keep it that way. Seriously. If there weren’t any witnesses, it’s his word against the kid’s.”

Project Veritas and founder James O’Keefe are known for breaking laws and lying in pursuit of their political agenda, union officials said in a statement Tuesday.

“Nevertheless, the deceptive video clips that O’Keefe has posted are troubling and we are committed to a swift, full and fair investigation so that all appropriate actions can be taken,” the union said. “When the facts are known, we will act swiftly in the best interest of our students and consistent with the high standards we uphold for all educators.”

Mankini did not respond to a request for comment Tuesday.

It is illegal in California to record or eavesdrop on a conversation without the consent of all parties. It does not appear Mankini gave consent, union officials said. Project Veritas representatives said they had obtained the footage legally.

San Francisco school district officials also said they investigate all complaints of wrongdoing, but added that Mankini has not been a classroom teacher for several years.

The comments that Mankini appears to make in the video “are very disturbing,” said district spokeswoman Gentle Blythe. “We have grave concerns about the behavior Mr. Mankini references and encourage any former students, staff or family members who may have experienced mistreatment from Mr. Mankini or any other district employee to report their concerns immediately.”

The tape is among a series of Project Veritas videos going after school labor unions, said a spokesman for the group, Nick Evangelista. He said the San Francisco video had been edited, but nothing was taken out of context.

The video was recorded as part of a fishing expedition, Evangelista said, and was not prompted by any allegations against district teachers.

Jill Tucker is a San Francisco Chronicle staff writer. Email: jtucker@sfchronicle.com Twitter: @jilltucker