The Green Party says nearly 90% of councils don't mention Te Tiriti o Waitangi in their citizenship ceremonies.
One of its MPs, Catherine Delahunty, is seeking to update the Citizenship Act to ensure new New Zealanders are told about the nation's founding document.
She says in many councils, the closest to a mention of Tangata Whenua is the singing of the national anthem in Te Reo Maori or the gifting of a native plant.
Ms Delahunty says acknowledgement of the Treaty by local authorities is random.
She says places such as Porirua appear to be very aware of culture and do a good job.
Catherine Delahunty says just over 10% of councils currently make specific reference to Te Tiriti o Waitangi - and should be applauded for doing so.
She says some regions have strong relations with tanagta whenua and have kaumatua speaking about the Treaty.
But Ms Delahunty says other districts don't think it's relevant - which could be a reflection of their relation with iwi or the understanding of the document signed between the Crown and Maori in 1840.
She carried out her research by writing to all the local authorities and asked them how their citizen ceremonies were conducted.