The Labour MP behind the bid to legalise gay marriage expects the debate to divide grandparents and grandchildren.
With Labour MP Louisa Wall's Marriage (Definition of Marriage) Amendment Bill tipped for a final reading in May, same-sex marriage could be passed into law next year.
Ms Wall said the bill was a "talking point" with the potential to split families this summer.
"For me, it's an issue like the Springbok tour: you're either for it, or against it. I'm happy for it to be one of the topics of holiday conversation."
She said debate over marriage equality reflected a "generational issue", with pensioners proving to be the minority in opposition.
"And for me, the opportunity to get that cross-generational dialogue going is between grandparents and grandchildren.
"I think it provides a really good opportunity for older people to talk to younger people."
A recent Dominion Post readers' survey also reflected the divisiveness of the issue.
Of the 613 readers polled from December 13 to 20, 35 per cent identified themselves as being in support of same-sex marriage, while a further 35 per cent were against it.
Just under a quarter described themselves as "neutral" on the subject, while a further 6 per cent had no opinion.
The Futurescape Global Dominion Post poll had a margin of error of 4 per cent.
Those in opposition were much more vocal than those in favour. Fewer than a quarter of the 176 respondents who took the optional opportunity to expand on their opinions spoke out in favour of marriage equality.
Many defined marriage as being between a man and a woman, while several felt a civil union was sufficient recognition of gay couples by law.
Eighty-eight per cent of respondents were aged over 40.
"I think it is difficult for most people in my age group (late 70s) to accept that two people of the same sex can be ‘married'," wrote one respondent.
Someone else remarked that their stance against gay marriage was "just the way I was brought up", while another apologised for being "old-fashioned".
Grey Power New Zealand national president Roy Reid said a lot of older people were "reasonably conservative in their thinking", and agreed that some of the association's members would struggle to express support for marriage equality.
"Most older people hold on to what they were taught was right and wrong from very early days."
Ms Wall said she could understand senior citizens' reluctance to endorse gay marriage. "For many people, what they've seen is what they understand - and they understand marriage to be between a man and a woman."
None of her parents' friends were openly gay when she was a child, she said. "You just didn't see it, growing up."
But she said that a lot of today's pensioners would have campaigned for homosexuality to be decriminalised in 1986.
"Obviously younger New Zealanders are a lot more accepting of marriage equality, but it's a minority even within that 80-plus cohort [that are in opposition]."
Mr Reid himself was "reasonably easy" about same-sex marriage. "It doesn't bother me if someone who holds those beliefs wants to get married."
Ms Wall's bill is now before a select committee, which will report to Parliament on February 28.
- The Dominion Post
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