A poll on capital gains tax out this week provided the first glimpse of the political impact of Prime Minister Jacinda Ardern's handling of the Christchurch mosque shootings.

The Reid Research poll was commissioned by Business NZ, and intended to gauge public support for capital gains tax.

It began on March 15 – the same day as the terror attack. It ran until March 23 – two days after Ardern announced the detail of gun reforms at her post Cabinet press conference.


As part of it, the 1000 polled were also asked which party they supported.

Those figures showed Labour very nearly cracked the 50 per cent mark for support.

Once those who did not give a choice of party are taken out, Labour was on 49.6 per cent, National on 41.3 per cent and NZ First and the Green Party were languishing on 2.3 per cent and 3.9 per cent respectively.

In the last Newshub Reid Research poll from February, Labour was on 47.5 and National was on 41.6 per cent.

The lift in Labour's support is hardly unexpected – Ardern was front and centre over that period and widely lauded for her handling of it.

During the last National government, its polling too would often lift after a major event such as the Christchurch earthquakes – often above 50 per cent.

It is more of a surprise it had not come at the expense of National, which has barely budged from February.

But that February poll was the lowest National had been in a decade. It had believed its support had rallied back up to higher in the 40s since that February poll was taken, based on its own internal polling.


It had regained traction as leader Simon Bridges hammered away at the capital gains tax, KiwiBuild and cost of living arguments.

If that was the case, it has again lost all that ground.

Prime Minister Jacinda Ardern. Photo / Mark Mitchell
Prime Minister Jacinda Ardern. Photo / Mark Mitchell

That points to a "soft" bunch of swinging voters, support which can be easily won – but equally easily lost again. Both sides will be trying to secure those for the longer term.

Ardern's actions over the last three weeks will have gone some way to help solidify that behind Labour. But this month will also bring something that could imperil it: the Government's decisions on tax reform.

Those in National looking for a silver lining are pointing to the likes of US President George Bush, former British Prime Minister Winston Churchill and Norway's former leader Jens Stoltenberg who led their countries in times of great trial, but ended up losing elections on bread and butter issues such as jobs and taxes.

They will need to take to that silver lining with elbow grease and a silver cloth, for at the moment Ardern seems untouchable.

For some time now, Bridges will find it hard to challenge any measures the Government takes which are a response to those attacks.

But this week made it clear that amnesty does not extend to politics overall.

The capital gains tax debate was not the only bogeyman to creep back out from under the bed after the hiatus following those attacks.

Kiwibuild is back, undergoing "recalibration". The teachers also voted against pay settlements again, presenting the possibility of further strikes.

The poll itself carries a warning for Labour. Even among Labour voters, support for a capital gains tax was low.

Even for a limited capital gains tax on property other than the family home there was only 53 per cent support among Labour voters.

That is long-standing Labour policy, and is the area Labour see as most politically palatable because it targets property speculators and the like.

Only one third of Labour voters believed a capital gains tax should be a priority, and a similar number believed it had damaged the Government.

Whatever the Government presents on tax will then be put to the voters to decide on in the 2020 election.

The worst news in that capital gains tax poll was for NZ First and the Greens, both of which were well under the five per cent threshold.

Labour's biggest obstacle on a capital gains tax may not be voter sentiment but NZ First which has now seen vast tracts of its usual anti-immigration platform swept out from under it by those mosque attacks.

If it is looking for a replacement platform, the answers to NZ First's dilemma may be found in the same poll.

• The Business NZ Reid Research poll of 1,000 voters was taken from March 15-23 and has a margin of error of +/- 3.1 per cent. 750 were interviewed by phone and 250 online.