[1] An explicit understanding of such a constitution can be developed through commentary by the judiciary, government committees or legal experts.
In such a constitutional system, all these elements may be (or may not be) recognized by courts, legislators, and the bureaucracy as binding upon government and limiting its powers.
"[2] A significant disadvantage, however, is that controversies may arise due to different understandings of the usages and customs that form the fundamental provisions of the constitution.
[1] Conversely, customs and practices that have been observed for long periods in an uncodified manner may be added to the written constitution at various junctures, such as in the case of the two-term limit for presidents of the United States.
This custom was observed for nearly a century and a half, unbroken, without any enforcement mechanism until it was ignored by Franklin Roosevelt, after which it was added to the written Constitution as mandatory de jure.
[9][10] The Constitution Act 1986 has a central role,[9] alongside a collection of other statutes, orders in Council, letters patent, decisions of the courts, principles of the Treaty of Waitangi,[7][11] and unwritten traditions and conventions.
Because the political system evolved over time, rather than being changed suddenly in an event such as a revolution, collapse of government or overthrow of monarchy, it is continuously being defined by acts of parliament and decisions of the courts.