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Symmetry Based Fairness

Treat equivalent cases equivalently unless a relevant asymmetry justifies different treatment.

The Diagnostic Story

Symptom: Comparable cases are being handled differently, but no one can clearly state which differences justify the different treatment. Exception records are sparse, invented after outcomes are chosen, or simply absent. Audits reveal unexplained variation after controlling for stated criteria. Policy language says cases are treated equally, but operational practice has developed hidden asymmetries that look like discretion to insiders and look like bias or arbitrary preference to everyone else.

Pivot: Define which cases are equivalent for the purpose at hand, constrain decision-makers to treat those cases the same, and require an explicit, reviewable rationale when treatment diverges—so that deviation from equal treatment is justified differentiation rather than undocumented discretion.

Resolution: Treatment of comparable cases becomes more consistent, arbitrary variation across reviewers, units, and time periods decreases, and the distinction between justified differentiation and unjustified inequality becomes auditable. The system gains legitimacy because deviations from equivalent treatment are reasoned and attached to the outcome record.

Reach for this when you hear…

[loan underwriting] “Two applications with the same financials got different rates last quarter—I need a documented reason for that difference or we have a fair-lending exposure.”

[academic review] “We approved that research protocol but rejected an almost identical one from a different lab, and the file contains no explanation of what the relevant difference was.”

[benefits administration] “The same exception has been granted to some employees and denied to others with identical circumstances, and nobody can point to a rule that explains it.”

Mechanisms / Implementations

  • Anti-Discrimination Check
  • Classification Fairness Review
  • Consistency Audit
  • Equal-Treatment Checklist
  • Exception Register
  • Policy Symmetry Test
  • Precedent Analysis

Abstractions this archetype builds on — directly (a source ingredient) or as a related pattern. Links follow the typed catalog namespace.

Built directly on (3)

Also references 7 related abstractions

Variants

Narrower or domain-specific specializations that share this archetype's core structure. Recognized variants are established; candidate variants are provisional.

Policy Symmetry Review · governance variant · recognized

Reviews whether a policy treats equivalent cases the same across units, populations, time periods, or rule interpretations.

Precedent Consistency Review · governance variant · recognized

Compares a current case to prior analogous cases so departures from precedent require an explicit relevant difference.

Anti-Discrimination Symmetry Check · risk or failure variant · candidate

Tests whether identity, status, location, or group markers are changing treatment when they are irrelevant to the decision rule.

Reciprocal Burden Symmetry · governance variant · candidate

Checks whether burdens, duties, or obligations are distributed symmetrically among parties in reciprocal positions.