New York State United Teachers’ push to unionize teachers in charter schools will gain heightened visibility this afternoon when teachers at the Buffalo United Charter School hold a demonstration to bolster their efforts to join NYSUT.

Teachers at the Manhattan Avenue school voted twice to affiliate with the statewide teachers union — once unanimously and once with a 90 percent majority— but that effort has been stymied by a decision by a Public Employment Relations Board administrative law judge, said Barbara Coogan, a Buffalo United librarian who is instrumental in the unionization drive.

“We are not respected here —we do not have a voice at all,” Coogan said. “We are told what to do, and we have to do it. We are simply asking the board and the administration to do what’s right for the children and staff by allowing us to have a seat at the table.”

Last month, M. Lynn Fitzgerald, an administrative law judge, turned down the request of the Buffalo United Charter School Education Association for certification as the teachers’ bargaining unit.

Fitzgerald ruled that the teachers’ employment is “substantially controlled” by National Heritage Academies, a private, for-profit school management firm under contract to operate Buffalo United.

As a result, Fitzgerald said, the teachers are not covered by the labor relations provisions of the state’s Taylor Law accorded to public employees.

NYSUT is appealing that ruling, saying a similar case involving National Heritage Academies was decided differently in Brooklyn.

“The Buffalo United teachers have spoken out quite clearly that they want a voice in what happens to them on the job,” said Richard C. Iannuzzi, NYSUT president. “Their overwhelming response in favor of organizing should not be ignored. It is their legal right.”

School officials could not immediately be reached to comment.