Material-Fact Comparison Matrix¶

Method — instantiates Precedent-Guided Decision Governance

Compares the current and prior cases on rationale-linked factual dimensions and records which differences are material and which are not.

Version: v1 · 2026-08-24 · History
Mechanism #: 5089
Type: Method
Form family: Analysis, Modeling & Optimization
Solution family: Boundary & Scope Control
Problem family: Authority, Accountability, Legitimacy & Fair-Process Failure
Problem subfamily: Rules, Rights, Obligations & Consistency
Origin domain: Law & Governance
Instantiates: Precedent-Guided Decision Governance

Two cases can look alike on a dozen visible features and still differ on the single fact the earlier rule actually turned on — and they can differ on a dozen visible features while matching on the one that mattered. The Material-Fact Comparison Matrix is the method that separates these. It lays the current case and a candidate precedent side by side across a set of factual dimensions, but its defining discipline is that each dimension is admitted to the matrix only because the prior rationale makes it relevant — and each cell is scored not just "same/different" but "material/immaterial to the rule." A difference that the earlier reasoning never depended on is logged as present-but-immaterial; a match on a rationale-critical fact carries more weight than any number of incidental resemblances. The matrix does not decide the case; it produces a defensible finding about where the analogy holds and where it breaks.

Example¶

An auto insurer is deciding a total-loss claim on a flooded vehicle and reaches for a prior claim it paid on similar facts. The two claims share a great deal on the surface: same model year, same regional storm, same repair estimate exceeding book value. A naïve match would pay out. The comparison matrix forces the adjuster to first recover why the earlier claim was paid — the governing reason was that the floodwater reached the vehicle's electrical harness, making repair unsafe rather than merely uneconomic. That rationale dictates the dimensions that go into the matrix: waterline height relative to the harness, evidence of electrical intrusion, and whether the repair estimate reflected safety or cost.

Filled in, the matrix shows the current vehicle was flooded only to floor level, well below the harness. The model-year and storm matches, though real, are logged as immaterial — the earlier rule never depended on them. The one rationale-linked dimension diverges. The matrix hands the decision maker a clean finding: materially distinguishable on the fact the prior payout turned on, which is exactly the input a treatment decision needs to justify a different result.

How it works¶

The method's distinctive steps are about which columns exist and how cells are scored, not about reaching a verdict:

Derive the dimensions from the rationale, not the fact pattern. Before any comparison, the prior rule's governing reason is stated; only facts that reason makes relevant become matrix columns. Facts the rule never used are excluded or flagged as incidental.
Score each cell twice. Every dimension gets a same/different reading and a material/immaterial tag, so a real difference on an irrelevant axis cannot masquerade as a distinction.
Weight by rationale-criticality. A divergence on a fact the rule turned on outweighs many matches on decorative facts; the matrix makes that asymmetry explicit rather than letting a feature count dominate.
Output a located finding. The result is a map of where the analogy holds and precisely where it fails — not a follow/distinguish decision, which is made elsewhere on the strength of this map.

Tuning parameters¶

Dimension admission strictness — how tightly a fact must connect to the prior rationale before it earns a column. Strict admission guards against surface-similarity overmatch but can miss a fact whose relevance was latent.
Materiality threshold — how strong a difference must be before it is tagged material. A low threshold makes distinguishing easy (and manufactured distinctions likelier); a high one entrenches following.
Weighting scheme — whether rationale-critical dimensions are formally weighted or judged holistically. Explicit weights are auditable but invite false precision.
Precedent breadth — one candidate precedent per matrix or several compared at once. Multi-case matrices reveal which precedent fits best but grow unwieldy.
Abstraction level — how narrowly each dimension is framed, trading transfer against overreach.

When it helps, and when it misleads¶

Its strength is that it makes analogy inspectable. By tying every column to the governing reason, it directly attacks the archetype's two opposite failures at once — superficial overmatching and opportunistic distinction — because both require a fact to be treated as relevant that the rationale never blessed. It is a working instance of reasoning by analogy in the tradition Edward Levi described, where the whole game is deciding which similarities and differences the controlling rule makes count.^[1]

Its failure mode is that materiality judgments are themselves contestable, and a determined decision maker can gerrymander the dimension set — admitting a favorable axis, excluding an inconvenient one — so the matrix launders a predetermined result through an official-looking grid. It is also only as sound as the rationale it starts from: misread the earlier rule and every column inherits the error. The guarding discipline is to have the dimension set and materiality tags reviewed by someone who did not want the outcome, and to require that any newly-admitted "material" difference be shown to have plausibly changed the earlier result, not merely to be present.

How it implements the components¶

This matrix fills the similarity-analysis slice of the archetype:

material_fact_similarity_model — it is the model made operational: rationale-derived dimensions, dual-scored cells, and an explicit map of material versus immaterial difference.
holding_rationale_boundary — by requiring the governing reason to be stated before columns are drawn, it enforces the line between the rule that binds and the incidental facts that do not, letting only rationale-relevant facts into the comparison.

It stops at a finding. It does not choose a treatment verb (precedent_treatment_decision, held by Follow–Distinguish–Overrule Memo), rank the precedent's authority (precedent_authority_map, held by Precedent Authority and Validity Table), or find the cases to compare (precedent_retrieval_and_adverse_search, held by Adverse-Precedent Search Protocol).

Instantiates: Precedent-Guided Decision Governance — the matrix is where "like case" stops being an assertion and becomes a tested finding.
Consumes: Precedent Case Brief supplies the recorded rationale and facts each comparison is built from.
Sibling mechanisms: Adverse-Precedent Search Protocol · Follow–Distinguish–Overrule Memo · Precedent Authority and Validity Table · Precedent Case Brief · Precedent Change Notice and Transition Plan · Precedent Conflict Panel · Precedent Citation Graph · Precedent Consistency Audit

Editorial Notes¶

Form Classification¶

Form family: Analysis, Modeling & Optimization

Rationale: Material-Fact Comparison Matrix operates as a computation, comparison, model, or analytic representation used to infer, estimate, or choose because it compares the current and prior cases on rationale-linked factual dimensions and records which differences are material and which are not.

Independent corroboration: The frozen evidence defines Material-Fact Comparison Matrix as 'Compares the current and prior cases on rationale-linked factual dimensions and records which differences are material and which are not', so its operative form is Analysis, Modeling & Optimization.

Review outcome: Independent reviewer agreement; high confidence.

Origin Attribution¶

Primary origin: Law & Governance

Origin pattern: Single lineage

Present-day reach: Specialized

Rationale: Distinguishing cases by material facts is a canonical method of precedent-based legal reasoning.