Harmonised duty, devolved remedy

This is article 2 of 2 in The Roman Ledger series. Here is article 1.

The shop stood in Minturnae, leased from the town. Its smoke drifted into the building above. Aristo advised that the tenant could not lawfully discharge smoke into the upper premises unless he held a servitude entitling him to do so, and added, pointedly, that the municipality which had granted the lease would answer to the tenant for the loss. Ulpian preserved the opinion, and with it the observation that smoke, water and flying stone chips are all, in law, the same kind of intrusion.

It is a small case about a cheese shop. What makes it worth two thousand years of attention is not the ruling but its shape. Aristo did not begin by declaring a right to clean air. He began at the other end: with what the man upstairs could actually do, against whom, and on what basis. The right to be free of the smoke existed because an action lay to stop it. Remove the action and the right does not shrink, it disappears.

The first part of this article examined Município de Mariana v BHP, in which an English court applied a Brazilian statute of 1981 to make an Anglo-Australian parent company liable, on a test of control, involvement, financing and benefit, in a claim valued at some £36 billion. It ended with a question. Why does a European system capable of specifying corporate environmental conduct in thousands of prescribed datapoints deliver so little to those actually harmed, while a single foreign provision delivers that?

The answer is a matter of order of operations, and the Romans got it the other way round.

I. Remedies before rights

Classical Roman litigation ran through the formula: a short written instrument, settled before the magistrate, which framed the dispute for the lay judge who would decide it. Its parts were fixed. The intentio stated the claim, si paret, if it appears that the defendant ought to give or do such a thing. The condemnatio instructed the judge to condemn the defendant in a sum or absolve him. Around these clustered the demonstratio setting out the facts relied on, the exceptio raising a defence, and so on.

The consequence is easy to miss. The substantive right had no independent existence. It was stated inside the procedural instrument that vindicated it, and the question a Roman lawyer asked was never "do I have a right?" but "does an action lie, and in what terms?" Maine's formulation remains the best: substantive law has at first the look of being gradually secreted in the interstices of procedure.

This matters for what happened next, and here a common claim must be corrected before it can be used. Roman law did not apply uniformly across the Empire. Before AD 212 the ius civile governed Roman citizens while peregrines lived under their own laws, mediated by the praetor peregrinus and the ius gentium. Even after the Constitutio Antoniniana extended citizenship to almost all free inhabitants, local law and local practice persisted on a scale that generated its own scholarly literature, Mitteis's Reichsrecht und Volksrecht is the monument to the gap between imperial law and what provincial populations actually did. Provincial governors issued their own edicts. Western "vulgar law" diverged steadily from the classical texts.

What travelled, then, was not a code. It was a technique. A governor's court in a province and a praetor's court in Rome could run recognisably the same action because the provincial edict reproduced much of the urban praetor's, and because what was portable was the instrument itself, a formula naming a claimant, a defendant, a factual hypothesis and an instruction to condemn or absolve. Substantive divergence was tolerated to a degree that would be unthinkable in a modern union. Divergence in the form of action was not.

That is the Roman achievement worth borrowing: a common form of action across divergent substantive law.

II. The European inversion

European environmental law has done the opposite, and done it deliberately.

Article 288 TFEU provides that a directive binds as to the result to be achieved while leaving to national authorities the choice of form and methods. Applied to sustainability regulation, this produces a characteristic division. The substance is harmonised to an extraordinary degree of detail: the European Sustainability Reporting Standards were adopted as a Commission delegated regulation, directly applicable in every Member State without transposition, prescribing the datapoints, the double-materiality assessment and the value-chain reporting. There is no national discretion about what must be reported.

The remedy is another matter entirely. Sanctions, supervisory architecture, the identity of the competent authority, the availability of civil liability and the procedural rules governing any claim are left to twenty-seven legal systems.

It is worth being exact about what is and is not uniform here, because three different things are in play and only one of them has been harmonised.

The measure is uniform. Greenhouse gas emissions by scope, energy consumption in megawatt hours, water withdrawal in cubic metres from areas of water stress, the number of sites in or near biodiversity-sensitive areas, hazardous waste by tonnage: the standards prescribe what is counted, on what boundary, by which method, in which units, and in a tagged format that machines can read across the Union. A tonne means the same thing in Lisbon and in Tallinn.

The duty is uniform only in the thin sense that everyone must publish those figures. It is a duty to describe. It is not a duty to keep emissions below any level, to abstain from water stress, or to avoid harming a habitat, the standards set no environmental thresholds at all, and taxonomy alignment is a percentage, not a permission.

The consequence is not uniform in any sense. What happens to a company whose figures are false, or whose conduct is what the figures accurately describe, depends entirely on which national system a claimant or regulator can reach.

The Union has therefore harmonised the metric to the decimal place, harmonised the obligation to report it, and devolved the question of what follows when the underlying conduct causes harm. The one thing measured with real precision is the smoke. The rule about the smoke is somewhere else.

The result is a right whose value is determined somewhere other than where it was created. And because the value of a right is fixed at the point of remedy, a harmonised duty with a devolved remedy is not, in any operative sense, harmonised at all.

What the record shows

This is not a theoretical objection. The transposition history of the CSRD is the experiment already run.

The deadline expired on 6 July 2024. In September 2024 the Commission opened infringement procedures against seventeen Member States, Belgium, Czechia, Germany, Estonia, Greece, Spain, Cyprus, Latvia, Luxembourg, Malta, the Netherlands, Austria, Poland, Portugal, Romania, Slovenia and Finland, for failure to notify full transposition. Sweden received a reasoned opinion in December 2024. By March 2026 the picture remained ragged: Austria had only partially transposed, through legislation in force from 19 February 2026; Finland and Romania had legislated and were still assessed as non-compliant; in several Member States the directive was not in force at all.

The Commission's own explanation of why this mattered is the most damaging sentence available on the subject. Without transposition, it said, it would not be possible to achieve the necessary level of harmonisation of sustainability reporting, and investors would not be able to take companies' sustainability performance into account.

That is the Union conceding that a uniform substantive standard, unaccompanied by a uniform remedial route, delivers neither uniformity nor effect.

No horizontal direct effect

There is a further structural point, and it is the one that should trouble anyone who believes an EU environmental duty is a duty owed to those it protects.

The Court of Justice has held consistently that a directive cannot of itself impose obligations on a private party, and cannot be relied upon as such against an individual or a company. Directives have vertical direct effect against the State; they have no horizontal direct effect. Where transposition has not occurred, a person harmed by a company's conduct cannot invoke the directive against the company. The Court has softened the edges, national courts must interpret domestic law so far as possible in conformity with the directive, and a Member State that fails to transpose may be liable in damages to those who suffer loss as a result.

Consider what those doctrines are. Consistent interpretation and State liability are remedies invented after the fact to compensate for the absence of a remedy in the original instrument. Francovich exists because rights were created without actions. Sixty years of the Court's most inventive jurisprudence, direct effect, indirect effect, State liability, effectiveness and equivalence as limits on national procedural autonomy, is retrofitting: the construction of remedial architecture downstream of substantive rights that were promulgated without any.

A Roman lawyer would find the sequence unintelligible. One does not create the obligation and then, decades later, litigate one's way toward an action by which it might be enforced.

III. Two deletions

Set the European legislative record beside the litigation record described in Part I.

In 2022 the Commission proposed a directors' duty of care in sustainability matters, and a companion provision making directors responsible for establishing and overseeing due diligence. Read together they would have created a framework for the personal liability of directors. The Council opposed them and both were deleted in trilogue; neither appears in the enacted Directive.

In 2024 the Directive was nonetheless adopted with a harmonised civil liability regime, a common European route by which a person harmed could sue a company subject to the duty. In February 2026 that too was removed, along with the implementation duty, and the scope narrowed to undertakings with more than 5,000 employees and net turnover above EUR 1.5 billion. Civil liability was not abolished. It was returned to national law.

What survived both rounds was the obligation to report, the measure, prescribed in directly applicable standards to a degree of granularity without precedent in European company law, and unaccompanied by any threshold the measure must not exceed.

Europe has twice been offered the chance to attach a person and a remedy to an environmental duty, and has twice declined, while steadily increasing the detail of the description. More classification, less consequence.

IV. The missing rule

There is a second gap, and it is prior to the first. Even a uniform action needs a rule telling the court why this defendant answers for this harm.

Call it imputatio: the rule by which conduct or environmental change is legally attributed to a particular person. It governs operational control, parent-company control, value-chain responsibility, financing, material contribution, apportionment among multiple actors and the incidence of the burden of proof. It must be kept apart from two neighbours with which it is constantly confused. Accounting attribution assigns a quantity to an entity: it answers how much. Causal attribution links conduct to an outcome: it answers whether this caused that. Neither makes anyone answerable in law, which is what imputatio does and what liability requires. Scope 3 accounting is the clearest illustration of the confusion, an accounting convention pressed into service as a rule of legal attribution it was never designed to be.

The point is not rhetorical. Where a legal attribution rule exists, a court has something to apply and a claimant has something to plead; where it does not, the court has a quantity and no defendant. No volume of disclosure closes that gap, because disclosure produces the quantity, not the rule.

V. Why a director should care

A board reading this far may reach a comfortable conclusion: Europe considered a directors' duty and dropped it, considered a European cause of action and dropped that, and what remains is a reporting exercise. Less exposure. Good news.

That reading is wrong in five specific ways, and each of them costs money.

The gap does not reduce your liability. It fragments it. No harmonised cause of action does not mean no cause of action. It means twenty-seven of them, each with its own rules on standing, limitation, causation, disclosure, costs and collective redress. A single European action with defined elements would have been something a board could price, provision and insure. What you have instead cannot be modelled, because the answer to "what is our exposure" is now "it depends which Member State a claimant chooses, and we do not choose."

Claimants will pick the most favourable of the twenty-seven, not the average. Harmonisation sets a ceiling as well as a floor; devolution removes both. France's duty of vigilance legislation carries a vigilance plan obligation enforceable by injunction and in damages, and has been used against major energy groups. The Netherlands has a collective action regime under which foundations bring damages claims on behalf of classes, and Dutch courts have been prepared to hold that a parent owes a duty of care in respect of group emissions. Germany's supply chain statute drives administrative enforcement and permits unions and NGOs to litigate on behalf of affected persons. These regimes do not converge. A group with operations or subsidiaries across the Union is exposed to whichever is most claimant-friendly, and it takes only one.

You pay for the description and get no defence from it. This is the sharpest point, and it is the one boards consistently miss. In a properly constructed system, compliance with a mandatory standard would do some work for the defendant: a safe harbour, a presumption of due diligence, at minimum evidence of reasonable care. The European architecture confers none of these. Complying fully with the reporting standards gives you no defence to a claim in any jurisdiction. You bear the entire cost of the description and receive nothing back in the register where it would matter.

Worse: the description is discoverable, and it is written against you. The reporting standards require disclosure of value chain, impacts, governance arrangements, transition plans and due diligence processes. Part I of this article explained that under English law a parent's duty of care arises from what the parent held itself out as supervising, and that under Brazilian law an indirect polluter is identified by control, involvement, financing and benefit. Mandatory sustainability reporting produces, in a public and machine-readable form, precisely the evidence a claimant needs to establish either. Europe has compelled you to write the plaintiff's case and declined to give you the legal framework in which that same document could operate as a defence.

And the deletion of the directors' duty protected nobody. Removing the proposed provision did not create a European safe harbour for directors. It left directors' duties where they were: under twenty-seven national company law regimes, under sections 172 and 174 in the United Kingdom, and, as Part I set out, under the criminal law of whichever country the harm occurred in. A harmonised European duty would at least have had knowable content and a knowable standard of compliance. What was removed was not a burden. It was a definition.

The instability is itself a cost. A directors' duty proposed in 2022 and deleted in 2023; a liability regime enacted in 2024 and deleted in 2026; thresholds moved twice; timetables deferred. Boards are asked to make twenty-year capital allocation decisions against a regulatory regime with a four-year half-life, and the one element that has survived every round is the obligation to describe.

None of which is an argument for less regulation. It is an argument for regulation built in the other order.

VI. What would follow

The prescription is not more classification. It is to build in the other order.

Supply the action first. Where the Union creates an environmental duty, it should create in the same instrument a cause of action by which a person harmed may enforce it, with harmonised minimum rules on standing, limitation, disclosure and the apportionment of costs. Anything less is a right whose content is European and whose value is national.

Supply the attribution rule. A duty framed against "undertakings" is inoperable without a rule stating when control, financing or benefit makes a parent, a purchaser or a financier answerable. That rule is the hinge of every case actually litigated, and no European instrument currently contains one.

Prefer the regulation to the directive where the remedy is the point. The ESRS were made directly applicable because the Union wished the datapoints to be uniform. If uniform enforcement matters as much as uniform reporting, and the Commission has said, in terms, that it does, the same instrument should carry the same force.

State the remedial consequence on the face of every classification. Each framework should be required to say what it classifies, who bears the resulting duty, whether the classification creates an obligation, an evidential presumption or information only, who may rely on it in proceedings, and what follows from misclassification. Where the honest answer is "nothing", it should say so. A classification that determines nothing should not trade on the authority of one that does.

None of this requires substantive uniformity across Member States. That is the point of the Roman analogy, and its limit. Rome tolerated enormous divergence in what the law said, while insisting on a common instrument through which it was enforced. Europe has reversed the arrangement and is discovering, directive by directive and infringement by infringement, that the half it devolved was the half that mattered.

The man upstairs, and the boardroom

Return to Minturnae. The shop is leased from the town, the smoke is drifting upwards, and Aristo gives his opinion: no right to emit absent a servitude, and the municipality that granted the lease answers to the tenant for the loss.

Set out what that short answer settles. A claimant, identified. A defendant, identified. A rule of attribution, the emission is the tenant's, and the licensing authority answers on the lease. A legal basis: the absence of a servitude. And a remedy the man upstairs could actually obtain.

Five elements, resolved in four sentences, in a dispute about cheese.

Now ask the same five questions of a European group with a tailings facility, a refinery or a supply chain in a jurisdiction where something may one day go badly wrong. Who could bring a claim, a resident, a municipality, a foundation, a union, a public prosecutor? In which of the twenty-seven, or in England, or in the country of the harm? Under whose substantive law? On what rule of attribution, given that no European instrument supplies one and the applicable law will be chosen by the geography of the damage? And with what consequence, damages, injunction, remediation order, criminal charge against a nominee director?

A board can answer none of these from its reporting stack. Not one of those questions is addressed by a taxonomy alignment percentage, a double materiality assessment, a value chain map or a machine-readable filing. Those are measures. Aristo's five questions are rules. The apparatus quantifies the smoke to a standard of precision Rome could not have imagined, and is silent on every question about what may be done concerning it.

That is not a complaint about compliance costs. It is a statement about where the risk actually sits. The exposure that ended in a £36 billion finding against BHP came from a foreign statute reached through a jurisdiction rule, and it was proved out of board papers, capital allocation, nominee appointments, warnings received and deferred, dividends taken. The European framework contributed nothing to that outcome except, potentially, evidence. A board that has satisfied itself on reporting and stopped there has audited the description and left the liability unexamined.

So the practical instruction is the Roman one, and it is simply put. Ask the questions in the order Aristo asked them. Not what must we disclose, but who could sue us, where, under which law, on what rule of attribution, and for what relief, and then work backwards to what that implies for the standards you publish, the seats you fill on local boards, the assurances you record in your minutes, and the operations you tell the world you supervise.

Europe has spent a decade building an extraordinary machine for measuring smoke, and has twice removed the parts that would have told anyone what to do about it. Until that is corrected, the answer will keep arriving from somewhere else: from Brasília, from The Hague, from Paris, from a common law court applying a statute written in 1981.

Aristo never measured the smoke. He did not need to: he knew what rule governed it, whom it bound, and what the man upstairs could do. We have reversed the achievement. We measure the smoke to three decimal places, in tonnes, by scope, on a harmonised boundary, in a format a machine can read in every Member State of the Union, and we still cannot tell the man upstairs what he can do about it. Nor, for entirely different reasons, can we tell the board downstairs.

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