About
The Climate Action Ledger is an evidence-based record of what New Zealand’s governing parties have done on climate - so voters can see the track record behind the rhetoric.
Why this exists
Climate policy shapes electricity bills, land use, industry, and the risks communities face from extreme weather. Over election cycles, parties make big claims about their climate credentials - but what they actually did while in power is easier to forget than what they said on the campaign trail.
This site pulls governing-party climate actions since 2014-present into one open ledger: each entry is scored, sourced, and attributed to the parties responsible. The aim is impartial, defendable information that helps Kiwis compare recent track records and make more informed voting decisions.
We focus on decisions made in office, not opposition speeches. Scores summarise expected climate impact on a scale from -10 (major harm) to +10 (major win). The underlying sources for each action are provided so you can read the evidence yourself.
Methodology
How we decide what counts, how actions are scored, and how party scorecards are built.
Why 2014-present
The ledger covers governing-party climate actions from September 2014 to today. That window spans two National-led and two Labour-led periods - roughly six years under each major party’s leadership - so recent track records can be compared on a similar footing. It is also a particularly active stretch for New Zealand climate regulation: emissions pricing, carbon budgets, adaptation planning, and energy and transport decisions all intensified in this era, and many of those choices are still shaping policy now.
How actions are scored
Each qualifying action was scored on the expected net climate effect of the decision as taken - policy design plus reasonably foreseeable uptake - for long-term mitigation, adaptation, or climate governance. Campaign rhetoric and opposition speeches do not count. Diplomatic or political signalling counts only when it is likely to change investment, behaviour, or later policy paths.
Scores come from an expert panel. Members assigned values from -3 to +3 according to the following guidance:
- +3
Major positive
Economy-wide or major-sector durable emissions reduction, or foundational climate governance/adaptation strengthening
- +2
Positive
Clear material net benefit with meaningful scale, duration, or enforcement
- +1
Minor positive
Limited-scale benefit, enabling reform, or incremental strengthening
- 0
Neutral/mixed
Negligible, offsetting, or too uncertain
- -1
Minor negative
Limited delay, weakening, or headwind
- -2
Negative
Meaningful delay, rollback, lock-in risk, or institutional weakening
- -3
Major negative
Economy-wide or major-sector rollback, lock-in, or damage to core climate institutions
The seven-point scale lets reviewers indicate their assessed magnitude without false precision. Panel members were asked to skip actions they could not judge confidently. For each action we averaged the available scores, scaled by 10/3, and rounded to the nearest whole number to obtain the published score for each action, ranging from -10 (major harm) to +10 (major win).
Categories
Actions are tagged with climate categories: mitigation, adaptation, and governance.
- mitigationEmissions reductions, removals, or fossil phase-out
- adaptationClimate risk reduction, resilience, and climate finance for adaptation
- governanceInstitutions, targets, budgets, pricing frameworks, planning
What gets included
Each ledger entry is a single discrete climate action - a specific decision or event, not a whole programme. To be included, an action must meet all of the following:
- Climate relevance - a non-trivial effect on mitigation, adaptation, or the institutions that govern climate policy.
- Verifiability - at least one primary source (for example legislation, Gazette notice, or official release) or an authoritative secondary source that can be checked.
- Governing connection - it happened while the attributed party held a governing role, or it is a direct implementation or reversal of such a decision.
- Significance - at least one of: structural policy change; material public spending (around $10m or more); a decision in an emissions-sensitive sector; long-term lock-in; or use of an explicit climate policy instrument.
What we leave out
We do not score opposition speeches, campaign promises, or purely symbolic statements with no governing effect. Actions outside the 2014-present analysis window are out of scope, except where brief context helps explain an in-window decision. Parties that have not held governing or policy-steering roles in this period are omitted from the party list for now as there is no comparable governing record to score (see the Parties page).
How attribution works
Each action is attributed to the party or parties responsible for making or driving the decision at the time. Attribution is not always a single party name:
- Sole - one party clearly owned the decision.
- Primary - one party led, with limited involvement from others.
- Shared - responsibility was genuinely joint (common in coalitions).
- Support-only - a partner enabled the decision without leading it.
Where responsibility is shared, the action can count toward more than one party’s scorecard. Every attribution includes a short rationale so the choice can be scrutinised.
How the scorecards are built
Homepage and party scorecards sum the impact scores of included actions for each attributed party. Shared coalition actions contribute to each attributed party. Party totals are therefore not additive across parties, i.e. you cannot score a coalition (such as National + ACT versus Labour + Greens) by summing the scores for each coalition partner, as this would double-count shared actions. The optional Normalise by years in office setting divides each party's total by their years in governing roles during the 2014-present window, so longer and shorter spells in office can be compared more fairly.
Feedback
We welcome constructive feedback, including questions and corrections. If something looks wrong, incomplete, or unclear, please get in touch at info@carboncritical.org.
Who built this
Carbon Critical is an independent non-profit R&D lab based in Auckland, New Zealand. We use maths, software, and data science to build digital tools and solutions that support a cleaner and better future.
This website is part of that work - turning messy public records into something citizens can use to make informed voting decisions. Check out our website to find out what else we are working on.
Carbon Critical also runs the Net Zero Fund, supporting global charities working on climate solutions.