There's a wonderful chaos about a parliamentary conscience vote. Backbenchers hitherto unworthy of much interest are suddenly the equal of their leaders.
OPINION: Where ministers and party leaders held court as the arbiters on any vote, the dirt-trackers are quickly thrust into the limelight. Every single vote counts.
Until this week, an intriguing vote on the alcohol purchase age appealed as the best prospect for mayhem among 121 MPs emboldened by the freedom of their own conscience.
An odd matrix of options on the alcohol purchase age will confront MPs most likely next month, when the Alcohol Reform Bill finally reaches committee stages.
No-one is very confident that National's Nikki Kaye has the numbers to keep the age at 18. There is even less belief that Tim Macindoe's effort to shift the age back up to 20 can pass muster. The purchase age proposed in the bill - a split between 18 and 20 - seems likely to win out, even though it has few ardent backers.
If indeed chaos reigns and a split age emerges to nobody's particular glee, Sir Geoffrey Palmer will have every right to say I told you so. The former Law Commission president and constitutional purist has repeatedly called for conscience votes to be scrapped on alcohol issues. Alcohol laws are no longer a matter of religion or morality, Sir Geoffrey says, but much more so about balancing public health with individual freedom. Parliament has proven a more coherent manager of such matters when votes are cast down party lines, he says.
Few would doubt a conscience vote is the correct path for voting on Louisa Wall's "marriage equality" bill, however.
Unlike the Alcohol Reform Bill, it stands alone as a social measure that calls on little other than the moral or religious perspective of MPs.
A significant group of National MPs were dumbstruck by the bill when it emerged this week, and seemed initially unsure what they should say about it. But the debate being founded on a conscience vote ought eventually to tease out a more full, frank and wholly worthwhile discussion. For once, voters might learn something about what their representatives really think about issues that interest them and how that aligns with their own views.
But the gay marriage debate about to unfold in the months ahead will not just be important for thrashing out the merits of the arguments in detail. There are serious political implications at play here too - the cat that got the tongues of senior National MPs on Thursday afternoon when asked for their positions on gay marriage proved that.
They will remember that the bitter spat over the anti-smacking legislation - also born of a member's bill picked at random - is frequently counted among the key issues that broke Helen Clark's formidable grip on power. And that was even though the bill was not of Labour's making and National MPs also supported it after an amendment was added.
The "anti-smacking" bill was every bit a matter of conscience to most "Mum and Dad" voters. It went right into the homes of every Kiwi family. For many of those whose conscience said "no" to it, their disapproval was channelled through a growing frustration at Miss Clark's "nanny statism". Strong emotions were widely aroused and the bitterness needed a target - Labour and Miss Clark were it.
Gay marriage comes with similarly raging red flags for today's political leaders. The definition of marriage is an issue that lives in almost every home in one way or another, and there are fiercely held views on either side of the argument. The political context again has a Government already fighting fires on several other fronts.
IT'S difficult, with gay marriage, to see anything other than pratfalls for the Key Government to try (or perhaps just hope) to avoid. Perhaps the only thing for Messrs Key and Joyce to cheer from it would be the potential for gay marriage to put a rocket-launcher under the prospects of the Conservative Party, which it is likely to need for another term in 2014.
For Labour, there are also risks but plenty more potential rewards. Ms Wall herself has for a while been seen as a backbencher with potential, without ever having made a mark. As long as she is not outshone by the Green Party's Kevin Hague, a strong performance leading this bill would shift Ms Wall's stocks significantly.
But the real winner could be her leader, David Shearer. Gay marriage is set up perfectly for Mr Shearer as a platform from which to properly introduce himself to a voting public still mostly unsure (or even completely unaware) of him. Unless he lays it on ludicrously thick, Mr Shearer can hardly lose votes by advocating strongly for gay marriage. Polls indicate that roughly two-thirds are comfortable with the idea - it's safe to assume only a tiny minority of the third against would even dream of voting for a Labour Party whose deputy is gay.
The even better thing about this bill for Mr Shearer - just like the paid parental leave and Mondayising bills passed this week - is the rare chance it offers to actually achieve something of real substance on a national scale. It's prime ministerial stuff.
Mr Key, as leader of the opposition in 2007, brilliantly tipped the anti-smacking bill even further in his favour by adding a National Party amendment, then offering his party's support, and coming across all prime ministerial on it. He shared a stage with Miss Clark in which her familiar face absorbed the sharp end of public scorn, and Mr Key's fresher face collected an important badge of authority.
If he is good enough, Mr Shearer has a similar opportunity with gay marriage. He can't speak for his Labour colleagues, because they will have a conscience vote, but who cares? He can speak for himself - and the persistent lack of anything like a bond with the voting public demands he does more of that.
What's more, he can do it without much risk. He should be storming the altar.
- The Dominion Post