overturn
plain-language theorem explainer
The overturn definition removes a specified precedent from a legal corpus represented as a list of precedents each carrying an integer σ-weight. Legal theorists modeling stare decisis via σ-conservation would cite this when proving that removals strictly decrease total σ-charge unless an equivalent replacement is supplied. It is realized as a direct list-erasure step.
Claim. Let $C$ be a corpus (a list of precedents) and $p$ a precedent with σ-weight. Then overturn$(C,p)$ returns the list obtained by erasing the first occurrence of $p$ from $C$.
background
A Precedent is a structure with a string label, an integer σ-weight (1 for trial level, 2 for appeal, 3 for supreme), and an age in years. A Corpus is the list of active precedents. The total σ-charge of a corpus is the sum of these weights and is additive under list concatenation, as established by the sibling totalSigma definitions.
proof idea
The definition is a one-line wrapper that applies the standard list erase operation to remove the first matching entry from the corpus.
why it matters
This supplies the removal primitive used by overturn_decreases_sigma, which proves totalSigma(overturn C target) + target.sigma = totalSigma C under the membership and positivity hypotheses, and by the PrecedentStabilityCert structure that encodes the overall stability certificate. It implements the basic operation in the module's derivation of σ-conservation for precedent stability and the bound on constitutional amendment rates tied to the 45-year gap cycle.
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