Kapiarumala's lawyer Craig Tuck on Monday said he'd filed a defamation claim in the High Court in Hamilton, after failed attempts at mediation with the New Zealand Catholic Bishops Conference, effectively the Catholic Church in New Zealand.
"Just about everything possible has ben tried, to resolve this out of the courts.
"There's been mediation sought, it was initially accepted then declined.
"The action being taken really is a last resort to bring all parties to the table."
He said it was far from a typical employment dispute.
"Some of the arguments which have been raised... for instance, a priest has a calling, he's not an employee.
"He's not subject to the usual laws or rule of law in the country that he's working in."
Tuck said his client had also been to the Human Rights Commission and were now taking it up with the Human Rights Review Tribunal.
A spokeswoman for the New Zealand Catholic Bishops Conference said the group was unable to comment at this point because it was a matter for the Diocese of Hamilton and was the subject of legal proceedings.
The Catholic Church has been making waves in Australia this week too, as Cardinal George Pell, the finance adviser to Pope Francis, arrived on Monday to face trial on historic sex charges.