It's in the "Other forms of discrimination" => "Racial disharmony" section, so it's applied in the context of racism (there are other sections that dictate other acts such as sexual harassment etc). There is also another section on "131 - Inciting racial disharmony"
http://www.legislation.govt.nz/act/public/1993/0082/latest/D...
which references the previously mentioned section. But also followed up by
http://www.legislation.govt.nz/act/public/1993/0082/latest/D...
"No prosecution for an offence against section 131 shall be instituted without the consent of the Attorney-General."