Katherine
Jensen, University
of Auckland, Waipapa Taumata Rau
A recent
RNZ analysis of political advertising on Facebook and
Instagram revealed an intriguing pattern in who was seeing
the ads.
Of more than 500 ads National ran this
year, 92 were seen only by men, attracting up to 3.9 million
views and costing as much as $21,000. Only one was seen
solely by women – for a single day, at a cost of less than
$100 – and the party says it didn’t place
it.
ACT showed a similar tilt, with 14 ads seen
only by men and none solely by women. For the Greens, the
pattern was reversed: 13 ads were seen only by women and
none only by men.
Paid campaigning on Meta’s
platforms is
nothing new in New Zealand elections. What has changed
is how decisions about who sees those ads are
made.
At first glance, RNZ’s findings might
suggest parties are deliberately choosing to speak to men
and women separately. But that assumes parties themselves
determine who ultimately sees each
ad.
Increasingly, that isn’t necessarily the
case.
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Who decides who sees an ad?
For
much of the past decade, digital advertising was relatively
straightforward: advertisers selected audiences based on
factors such as age, gender or interests, and platforms
delivered ads accordingly.
That model has shifted.
Meta now leans heavily on AI to judge which ads are most
relevant to users. Its Andromeda
system narrows tens of millions of potential ads and
variations to a few thousand likely matches before ranking
them. Meta’s Advantage+
tools can also automate decisions about audiences,
budgets and ad placement.
This makes the
distinction between targeting and optimisation important:
advertisers choose who they initially want to reach, while
the platform learns who responds and increasingly delivers
ads to them.
The result is that a political party
can begin with a deliberately broad audience and still end
up reaching disproportionately more men, younger voters –
or people already inclined to agree with its
message.
Researchers have been documenting this
problem for several years. In 2019, a study found
Facebook’s ad delivery could skew audiences by gender and
race even when advertisers used inclusive
targeting.
Other research found voters
statistically less likely to support a party could cost two
or three times as much to reach, while campaigns had little
visibility over how those decisions were
made.
Similar pricing effects have appeared in
elections. An
analysis of ten Indian elections found Facebook charged
the governing Bharatiya Janata Party (BJP) lower advertising
rates than rival parties in nine of them, allowing it to
reach more voters for the same spend.
More
recently, a
study of the 2024 European Parliament elections analysed
more than 110,000 ads across 25 countries. Men were
significantly more likely to receive ads from populist and
far-right parties, even after researchers accounted for
advertisers’ targeting choices.
These studies
cannot tell us exactly what Meta’s current systems are
doing. Its technology continues to evolve, while outside
researchers have limited visibility into how ads are
selected and delivered. We can see who received an ad, but
establishing why is much harder.
Europe has
attempted to improve transparency. Since October 2025, EU
rules have required political ads to disclose their
sponsor, cost and use of targeting techniques. Meta and
Google responded
by stopping political advertising in the EU rather than
complying.
That illustrates a challenge for
regulators: stronger disclosure can improve transparency,
but global platforms can simply withdraw from smaller
advertising markets. Smaller parties and campaigners may
feel that loss most, given they have fewer cheap
alternatives for reaching voters.
Does New Zealand
need new rules?
Concerns about political
microtargeting are not always backed by strong evidence.
In a
randomised experiment involving 8,587 participants,
tailoring political messages to individual characteristics
did not make them significantly more persuasive than showing
everyone the same message.
The bigger issue is
transparency around how political advertising is
distributed.
New Zealand law requires election
advertisements to carry a
promoter statement, while spending limits and reporting
requirements apply during the regulated period. But these
rules say little about how an ad’s audience was
selected.
For digital advertising, that leaves two
important questions: who did the party ask the platform to
reach and who did the platform actually show the ad to? A
party may select a broad audience, but the platform can
still concentrate delivery among people it predicts are most
likely to respond.
Greater disclosure could help
close that gap. Parties and promoters could publish the
targeting settings used for political ads, while platforms
could provide aggregate data showing who actually received
them.
This would make it easier to distinguish
deliberate targeting by a political party from optimisation
by the platform.
Voters can also get a broader view
of the campaign than their feeds provide. Meta’s
Ad Library allows anyone to search the political ads a
party is running, including those they might otherwise never
see.
Election advertisements should also carry a
promoter statement, while political advertisers on Meta must
be authorised and labelled “paid for
by”.
Ultimately, a social media feed is a sample
rather than a summary of an election campaign. It is
influenced partly by whoever paid for the advertising and
partly by a system predicting what will hold someone’s
attention.
People of different ages, genders and
browsing histories may therefore see very different
campaigns. Party websites, news coverage and ad libraries
can help fill in what is missing.
Katherine
Jensen, Professional Teaching Fellow, Business School,
University
of Auckland, Waipapa Taumata Rau
This article is republished from The Conversation
under a Creative Commons license. Read the original
article.
