The secondary teachers' union is defending a teacher suspended for supporting students in favour of same-sex marriage.
Science teacher Nigel Studdart was stood down on Wednesday by Pompallier College, a Catholic school in Whangarei.
Mr Studdart told the PPTA he was suspended for supporting students opposed to comments by the college's principal about gay marriage and gay parenting.
Principal Richard Stanton set out his religious objections to both in the school's August newsletter.
Radio New Zealand understands that Mr Studdart encouraged students to wear rainbow wristbands in support of the gay community and moderated a Facebook page they set up to air their views.
The PPTA says teachers accept that they must not undermine the special character of the school that employs them, as long as that does not involve a breach of human rights.
The union says it will always defend a teacher who risks their job by advocating for students, because that is the essence of professionalism.
It says it is in discussion with Pompallier College and its board of trustees.