Emission data occupy a special position within the Open Government Act (Woo), as confirmed in a recent ruling by the Administrative Law Division of the Council of State (the Division). An administrative body cannot simply refuse disclosure of this data. In this blog, we set out the rules for disclosure of emissions data under the Woo and discuss the Division's September 24, 2025 ruling.
Anyone can make a request for public information to an administrative body under the Woo, a so-called Woo request (Article 4.1 Woo). If an administrative body receives a Woo request, it must, in principle, disclose the requested information. Disclosure may only be omitted if one of the exceptions in article 5.1 or 5.2 Woo applies.
Part of environmental information relates to emissions into the environment. This category of environmental information, "emissions data," is subject to broader disclosure obligations. Thus, the exceptions in Article 5.1 do not apply when emission data are involved (Article 5.1 paragraph 7 Woo).
The background to this provision and the special regime for emissions data, is in the Aarhus Convention and the Aarhus Regulation (1367/2006). Among other things, the Aarhus Convention gives citizens and organizations the right of access to environmental information. The Aarhus Regulation gives effect to the Aarhus Convention. It follows from the Aarhus Convention and the Aarhus Regulation that grounds for refusal of disclosure should be interpreted restrictively if the information requested relates to emissions data. Initially, when the Woo was drafted, it was intended to include emissions data under the active disclosure obligation of the Woo, so that the government must disclose this information on its own accord even without a request. In the end, such an active disclosure obligation was not included in the Woo, and the new article 5.1 paragraph 7 Woo was chosen (Appendix to Parliamentary Papers I 2021/22, 33328, AB, p. 96). For more information on the active and passive disclosure obligation, please refer to our earlier blog.
It specifically concerns emissions into the environment. Environmental information can appear in documents about, among other things (Article 19.1a of the Environmental Management Act):
the condition of elements of the environment, e.g., air, water, soil, land and natural areas;
factors in the environment, such as substances, energy, noise radiation or waste that (probably) affect elements of the environment;
measures that relate or may relate to the state of elements of the environment or factors in the environment, such as policies, legislation, plans, programs, environmental agreements or activities;
reports on the application of environmental legislation;
cost-benefit and other economic analyses used to take action on the state of elements of the environment or factors in the environment;
the state of human health and safety, including the contamination of the food chain, conditions of human life, valuable cultural sites and structures, in so far as they are affected by the state of elements of the environment or through these elements by factors, measures or activities.
Not all environmental information is also information about emissions. There is much case law on what does and does not constitute emissions data. It includes not only data on actual emissions, but also data on the impact of those emissions on the environment (ABRvS Jan. 27, 2021, ECLI:NL:RVS:2021:153, para. 6.3). For example, advice regarding follow-up steps in dealing with nitrogen may contain environmental information that qualifies as emissions data (Rb. Midden-Nederland January 21, 2024, ECLI:NL:RBMNE:2024:676, r.o. 15). Also, for example, information about animals and the places where animals are kept can be data that relate to emissions (Rb. The Hague December 17, 2024, ECLI:NL:RBDHA:2024:22792, r.o. 3.1 & 6).
On the other hand, for example, the prices charged by a municipality for the sale of biomass supply were not covered by emissions data because they did not concern actual emissions or influences of emissions on the environment that would allow the public to check whether the governing body's assessment of actual or foreseeable emissions was correct (Rb. Gelderland Feb. 7, 2024, ECLI:NL:RBGEL:2024:594, r.o. 6.1-6.2). Similarly, data that is not plausible that it affects or is likely to affect the environment does not fall under emissions data (Rb. Amsterdam 9 July 2024, ECLI:NL:RBAMS:2024:4262, para. 17).
On Sept. 24, 2025, the Division ruled that Minister Wiersma of Agriculture, Fisheries, Food Security and Nature must disclose information about farms within two weeks (ABRvS Sept. 24, 2025, ECLI:NL:RVS:2025:4557).
Four journalists had submitted a Woo request to the minister (then Piet Adema, now Femke Wiersma) in 2022 and 2023. In their Woo request, they requested company data from 2010, 2015, 2020, 2021 and 2022 of all livestock farms in the Netherlands. The purpose was to use this to calculate how effective the nitrogen policy is. The journalists had asked for addresses of all livestock farms in the Netherlands, the number of registered farm animals per farm and the type of barn in which the animals were kept.
The minister had allowed third-party interested parties to submit views. On May 4, 2023, the minister finally decided to disclose the requested emission data. The Dutch Dairy Farmers Union (NVM) objected to the disclosure. In a decision on objection dated Feb. 14, 2024, the minister declared the objection manifestly unfounded.
On January 13, 2025, the new minister then decided to withdraw the earlier decision on objection. The reason the minister gave for this was that she felt that the viewpoint procedure should be set up differently. At the start of the opinion procedure, the Minister had informed interest groups and published about it in the Government Gazette. That, according to the Minister, was insufficient to reach a larger group of third-party interested parties about the proposed disclosure.
The Overijssel court did not go along with this and considered that the minister should not have taken the revocation decisions (Rb. Overijssel July 10, 2025, ECLI:NL:RBOVE:2025:4640; Rb. Overijssel 10 July 2025, ECLI:NL:RBOVE:2025:4639; Rb. Overijssel 10 July 2025, ECLI:NL:RBOVE:2025:4638). The court considered that it was established that emissions data existed and that redoing the viewpoint procedure would not lead to a different outcome. Therefore, the court also ruled that the minister's actions could not be understood as anything other than an action to delay disclosure of the requested data, which was labeled an abuse of rights. In line with this, on another Woo decision that had already acquired formal legal force (the decision had already been irrevocable for a year), the civil judge of the District Court of The Hague ruled that the minister had to disclose the requested information within two weeks on penalty of a fine of 50,000 euros per day with a maximum of 1 million euros (Rb. Den Haag 4 Sept. 2025, ECLI:NL:RBDHA:2025:16439). The minister wanted to wait for the rulings of the Division. The court considered that there were no valid grounds to refuse disclosure and that the public should be able to be informed about the effectiveness of the nitrogen policy.
The Division agrees with the aforementioned rulings of the Overijssel District Court on July 10, 2025. The opinion procedure followed prior to the disclosure decision was carefully and fully carried out. There is no basis for repeating the procedure. According to the Division, farm addresses, the number of animals kept and the type of stall fall under emissions data. Although the Division understands that livestock farmers are concerned about safety and operations (for example, because of actions by animal rights activists), the Woo provides no room for personal interests to weigh in on emission data. However, there was no abuse of rights by the Secretary of State, according to the Division.
On the same day as the ruling, Minister Wiersma responded with a letter. In it, she indicated that she had decided to make the data public within two weeks.
For companies that have to deal with environmentally sensitive information and have to provide this information to the government, it is essential to investigate whether this information must be made public or not. When receiving, for example, a request for an opinion on a draft Woo decision, it is therefore also advisable to find out (or have someone find out) very precisely what information does and does not fall under emissions data. Although emissions data must always be disclosed, companies can still object to the disclosure of (environmental) information that does not fall under the category of "emissions."
