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the counterfactual · economic damages

Causation versus damages.

Between the conduct and the loss sit the economy, the competition and the plaintiff’s own decisions. An analysis that ignores them does not survive.

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What is the economic harm?

Start a conversation with Cournot, the Institute’s damages concierge, already scoped to causation vs. damages. Pick a starting point, or describe the dispute directly.

Cournotcausation vs. damages · a diagnostic, not a damages opinion
Tell me about the loss and what else was happening in the period: the market, competitors, anything inside the business. I'll help you think about what needs disaggregating and how. The legal causation standard is counsel's question.

Every damages claim contains a causal assertion: the gap between the actual world and the but-for world is attributable to the conduct. The standard rebuttal is not that there was no gap, but that the gap has other parents. The economy turned. A competitor launched. Customers changed their habits. The plaintiff mismanaged something. Some of these will be true in almost every case, because businesses operate in moving environments, and the damages analysis that fails to engage with them fails entirely: an expert who attributes the whole gap to the conduct without addressing the alternatives has produced the version of the opinion most likely to be excluded as speculative. Disaggregation is the discipline of dividing the observed loss among its causes, by regression controls, by staggered timing, by market-wide benchmarks, or by explicit carve-outs, and it is where the economics of a damages case and the law of causation meet. What must be proven, and to what standard, is counsel's domain. What can be separated, and with which tools, is the economist's, and the answer determines whether the claim arrives in court as a number or as a hope.

mechanisms

Where the gap gets divided.

Each alternative cause is either addressed in the model or waiting in the rebuttal.

Market-wide movement

Recessions, demand shifts, sector shocks. Controlled with indices, benchmarks and comparator firms exposed to the same conditions.

Competitive entry

Sales lost to a lawful competitor are not damages. Timing and share evidence separates entry effects from conduct effects.

The plaintiff’s own conduct

Execution failures, strategic choices, underinvestment. The defense will document them; the analysis must account for them.

Intervening events

A pandemic, a supply shock, a regulatory change mid-period. Ignoring one visible to everyone forfeits credibility generally.

Regression controls

Variables for the alternative causes, so the conduct’s coefficient measures the conduct. The standard modern tool, and itself attackable on specification.

Explicit carve-outs

Where a cause cannot be modeled, removing its plausible effect openly. Less precise, often more credible than silence.

methodology

What the evidence shows — and what we examine.

How the Institute approaches the causation question.

Alternative-cause inventoryA deliberate list of everything else that could explain the loss, compiled the way the defense will compile it.
Control strategyWhich alternatives can be handled in the model, which need benchmarks, and which require explicit carve-outs.
Timing analysisWhether the loss appears when the conduct appears, and moves when it moves. Chronology is underused evidence.
The legal boundaryWhat causation standard applies and who bears it is law. The Institute maps what the economics can and cannot separate.
what's at stake

What disaggregation decides.

Often the difference between an admissible claim and an excluded one.

whether the opinion survives challenge how much of the gap remains as damages what market and competitor data is needed exposure to the speculation attack the credibility of the whole analysis whether econometric expertise is required

The all-or-nothing attribution is the classic exclusion.

Assigning one hundred percent of a loss to the conduct, in a period when the market fell and a competitor entered, is the fact pattern behind a large share of successful challenges to damages experts. The disaggregation does not have to be perfect. It has to exist, and be reasoned.

common questions

Causation and disaggregation: practical questions.

Does the expert have to disaggregate every possible cause?

Every material one that the evidence fairly raises, which is a practical standard rather than an infinite one. Nobody excludes an opinion for failing to model a trivial influence. What draws exclusion is silence on the obvious: an industry downturn visible in any index, a competitor whose entry the plaintiff's own documents complain about, a product failure covered in the trade press. The working test is adversarial: list the alternative causes the defense will present, and make sure each one is either controlled for in the model, shown to be immaterial, or explicitly carved out with a stated basis. An acknowledged limitation is a defensible position. An unacknowledged one is a trap that has already been set.

How does regression actually separate causes?

By estimating the relationship between the outcome and each candidate cause simultaneously, so the effect attributed to the conduct is what remains after the controls have claimed their share. A model of the plaintiff's sales that includes market demand, competitor activity and seasonality alongside a variable for the conduct period asks the data a precise question: how much worse were sales than the controls predict? Done well, this is the most rigorous disaggregation available. Its integrity depends on specification, controls that are actually exogenous, a form that fits the clean period, results robust to reasonable alternatives, and those choices are themselves the subject of expert dispute, which is why serious matters often put an econometrician behind the number.

What about causes that cannot be modeled?

They get handled openly or they get handled by the other side. Some influences resist quantification: a key employee's departure, a reputational event, a strategic misstep with no clean market analogue. The credible options are explicit. Bound the effect and carve it out. Present the damages under alternative assumptions about it, and let the fact-finder choose. Or explain, with reasons, why its effect is immaterial or already captured elsewhere in the model. What fails is the fourth option, silence, because an omitted cause does not disappear; it reappears in the rebuttal report with the defense's preferred magnitude attached, and by then the plaintiff's expert has lost the chance to frame it.

Is causation the lawyer’s problem or the economist’s?

Both, divided along a line worth drawing explicitly at the start of the engagement. Whether the conduct legally caused the harm, proximate cause, foreseeability, the standard of proof, is counsel's question and no economist should opine on it. Whether the observed loss is economically attributable to the conduct rather than to the market, and in what proportion, is analytical work, and it is where damages experts earn or forfeit admissibility. The two interact: the legal theory defines which harm matters, and the economic disaggregation shows how much of that harm the evidence supports. Matters go wrong when each side assumes the other has the question covered, and the gap surfaces for the first time in the opposing expert's report.

related

Related specialization areas & resources.

List the other causes before the defense does.

Describe the loss and the period. The Institute will help you see what has to be separated, and what tools can do it.

Cournotdiagnostic · not a damages opinion
Tell me about the loss and what else was happening in the period: the market, competitors, anything inside the business. I'll help you think about what needs disaggregating and how. The legal causation standard is counsel's question.