The Dutch government lodged an appeal last month against The Hague District Court's ruling on 24 June that required it to make more-drastic cuts to the country's greenhouse-gas emissions (see K. Purnhagen Nature 523, 410; 2015). The government's appeal seems to be buying time while the courts decide, which demonstrates the weakness of using lawsuits as a policy tool for climate change.

The climate law has been hailed as marking a new era of environmental activism that could spark similar cases in other countries. Critics have warned against undue politicization of the judiciary, which could inhibit nations from entering into binding international commitments.

The Dutch appeal is likely to be based on the government's right to determine policy, on whether the Kyoto Protocol can have such far-reaching effects and on the way the District Court has defined the state's duty of care. Both parties intend to take the case to the Dutch Supreme Court, which could take several years.

Meanwhile, the government is also awaiting the outcome of several studies before launching any policy proposals. This will not be until next summer at the earliest, so the general elections in March 2017 could offer a faster and more effective means of bringing about policy change.