As a result, the declaration's ratification by the British Parliament in 1836, officials in the Colonial Office determined in 1839 that a treaty of cessation would need to be signed with Māori for the British Crown to acquire sovereignty over New Zealand. The Treaty of Waitangi was signed in 1840 by representatives of the British Crown and over 500 Māori chiefs, and is considered the founding document of the nation. The Treaty identifies the Crown's right to "kawanatanga", or "governorship", leading one Māori academic to argue that "kawanatanga", or Her Majesty's Government in New Zealand, is party to the treaty.