In September 2016, the German parliament unanimously adopted the Paris Agreement. The government then translated Germany’s commitments under the agreement into a Climate Protection Law, which was approved by the Bundestag in November 2019 with a wide majority, making Germany the first country in the world with a greenhouse gas neutrality plan. By 2030, carbon emissions were to be cut 55 percent compared with levels in 1990, and a state of net greenhouse gas emissions was to be reached by 2050.
Yet in April this year, the country’s highest court unanimously — and stunningly — rejected key parts of the law as unconstitutional.
The court’s reasoning has implications far beyond Germany or Europe. Critics justifiably charge that United Nations agreements are not enforceable: more elusive road maps of intent rather than precise travel plans. The German Supreme Court has now given teeth to the Paris Agreement by requiring the government to detail how it will make Germany climate neutral and when. In an unusual case of positive rights’ adjudication, it also decided that the economic burden must be spread equitably from now to 2050.
Four aspects of the court’s decision represent milestones in constitutional law.
Firstly, the court accepted the construct of a climate budget as formulated by the UN Intergovernmental Panel on Climate Change (IPCC): “Limiting global warming requires . . . staying within a total carbon budget.” Based on this decision, the court stipulated that each human being is entitled to the same share of the amount of CO2 that can still be emitted if heating is to be kept below 1.5 degrees Celsius; and that this remaining amount must be shared equitably among all the world’s inhabitants, including between current and future generations.
This striking international and intergenerational equity determination requires the German government to develop, by 2022 at the latest, considerably more ambitious climate targets, measurable benchmarks and precise timelines. The court does not say so, but such planning will benefit how industry adjusts within clear guardrails. Implicitly siding with those climate activists who consider the Paris Agreement only a starting point, the court defines as the constitutionally required minimum standard limiting global heating to 1.5°C rather than the more moderate goal of “well below 2°C.”
Secondly, the court redefined the constitutional principle of “freedom.” It recognized that both global heating and climate mitigation constrain individual rights, the exercise of which — to shop, fly, drive, surf the Internet, eat meat and cheese, reside in ample space — emits CO2 and thus reduces the amount that future generations can emit. The scope of freedom available to future generations is more constrained than it would be if today’s consumption were less extravagant. Weighing the unavoidable trade-offs, the court determined that the greater threat to freedom results not from radical climate policy but from global heating.
The current generation interferes with the rights of future generations by allowing them to generate too many greenhouse gas emissions now, while deferring obligations of reductions to the future. The trivial benefits of halfhearted mitigation for the current generation impose unacceptable losses for future generations. And since the climate budget is not a matter of opinion but of physics and mathematics, the court pledges to ensure that the burdens will be distributed equitably. Intergenerational fairness will be legally enforced, especially since future generations will have to shoulder not only a cannibalized nature but also the vastly increased financial onus of climate mitigation and adaption.
Thirdly, pre-empting the argument that science is still evolving, the court requires policy to be based on the best currently available scientific knowledge and to be adjusted as more facts become available. The government must accept the authority of science. It may not err on the side of doing too little or hope for a technological deus ex machina to save the day. John Kerry, the United States climate envoy, in an interview with the BBC on May 16 acknowledged that 50 percent of the carbon reductions that are needed to get to net zero will come from technologies that have not yet been invented. The German Constitutional Court would frown upon such a stunning — reckless, actually — admission.
Fourthly, the court emphasized the triple obligation of the German government to contribute its fair share to the mitigation of global heating by reducing national emissions, to provide financial or technological transfers enabling the reduction of emissions elsewhere in compensation for its remaining unfulfilled responsibility and to leverage its foreign policy in pursuit of global solutions to a global problem.
The court categorically ruled that laziness on the part of some countries does not justify underperformance of others. Even if Germany accounts for only one percent of the world’s population and two percent of current global greenhouse gas emissions, it must pull its weight and, since global heating is an international public policy challenge, Germany must make emission reductions a foreign policy priority. Fairness, whether nationally or internationally, is crucial. So is the inverse: inequitable economic conditions must be addressed on their merits, unrelated to the challenge of global heating.
Working on global warming is not a pursuit that encourages optimism, but the decision of the German Constitutional Court is an important sign that the ground is finally shifting. Another rather conservative institution, the International Energy Agency, planted the second environmental wake-up bombshell recently. Its flagship report issued in mid-May noted that the rate of energy efficiency improvements will have to triple that of the last two decades and that most countries’ emission reduction pledges “are not yet underpinned by near-term policies and measures.”