Although the big questions relating to the franchise were largely settled by the end of the nineteenth century, there have been some important changes in more recent decades, in particular the lowering of the voting age.
As in most other democracies, the voting age - or 'age of political maturity' - in New Zealand had always been 21. By the 1960s, however, there was mounting pressure throughout the Western world for it to be reduced to 18. This was partly a result of demographic change and the expansion of secondary and university education.
But it was also partly a response to the growing student protest movement against the Vietnam War.
Young people argued that if 18 year olds were mature enough to fight in wars (and especially if they were drafted into the army, as in the United States), then they were old enough to have a say in electing their government. Many politicians agreed that it would be better if young people channelled their energies into mainstream politics rather than protest on the streets.
Between 1969 and 1974 the voting age was lowered to 18 in Britain, the United States, Canada, Australia and other countries. New Zealand reduced the age in two steps, to 20 in 1969 and then to 18 in 1974.
The franchise was altered again in 1975 to allow all permanent residents to vote, whether or not they had New Zealand citizenship (although only New Zealand citizens can serve in Parliament).
One hundred and sixty years after the first election in 1853, New Zealand's electoral system now gives virtually everyone over the age of 18 the opportunity to have a say in electing their parliamentary representatives.
Fight for the Right
Governments in New Zealand and elsewhere had long acknowledged a link between the vote and military service - that is, between the rights and responsibilities of citizenship. During both the First and Second World Wars, special laws were passed to enable all New Zealand military personnel to vote in elections, whether or not they were 21 years old.