Presume until rebutted

Intent

I want to keep a presumed status until a rebuttal is presented.

Correct formFrozen execution sceneBoundary

Wrong form and why it stays silent

Incorrect form

// unless convicted(p) якобы выводит not innocent(p).

A blocking proviso lifts the presumption but does not assert the opposite. A contrary proviso must explicitly name then not innocent(p).

Correct form

Minimal executable witness below.

Arxo Law

language "law.core" version "0.2";
package recipes.d.r01 version "0.1.0";
namespace "urn:recipe:d-evidence:01";

entity Person;
relation accused(p: Person);
relation convicted(p: Person);
relation innocent(p: Person);
presumption Innocence(p: Person) { when accused(p); presume innocent(p); unless convicted(p); }

Frozen execution scene

In the table P and Q are different entities of the page, C is a case; full identifiers are pinned in the scenes.

Input on 13.09.2026 (a different date is named in the scene)	Question	Answer
without rebuttal	truth(innocent(P))	TRUE_ONLY / COMPUTED
proviso blocks	truth(innocent(P))	NEITHER / COMPUTED
without the condition	truth(innocent(P))	NEITHER / COMPUTED
without the proviso	truth(innocent(P))	TRUE_ONLY / COMPUTED

presumption holds without rebuttal

Arxo Law

test "presumption holds without rebuttal" {
    given {
        context {
            legal_time @2026-09-13;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }
        assert accused(entity_ref("urn:recipe:d-evidence:01:p"));
    }
    evaluate truth(innocent(entity_ref("urn:recipe:d-evidence:01:p")));
    expect truth_status == TRUE_ONLY;
    expect evaluation_status == COMPUTED;

}

blocking exception suspends presumption

Arxo Law

test "blocking exception suspends presumption" {
    given {
        context {
            legal_time @2026-09-13;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }
        assert accused(entity_ref("urn:recipe:d-evidence:01:p")); assert convicted(entity_ref("urn:recipe:d-evidence:01:p"));
    }
    evaluate truth(innocent(entity_ref("urn:recipe:d-evidence:01:p")));
    expect truth_status == NEITHER;
    expect evaluation_status == COMPUTED;

}

missing trigger gives neither

Arxo Law

test "missing trigger gives neither" {
    given {
        context {
            legal_time @2026-09-13;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }

    }
    evaluate truth(innocent(entity_ref("urn:recipe:d-evidence:01:p")));
    expect truth_status == NEITHER;
    expect evaluation_status == COMPUTED;

}

removed exception restores presumption

Arxo Law

test "removed exception restores presumption" {
    given {
        context {
            legal_time @2026-09-13;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }
        assert accused(entity_ref("urn:recipe:d-evidence:01:p")); assert convicted(entity_ref("urn:recipe:d-evidence:01:p"));
    }
    evaluate truth(innocent(entity_ref("urn:recipe:d-evidence:01:p")));
    expect truth_status == TRUE_ONLY;
    expect evaluation_status == COMPUTED;

}

The counterfactual program differs only by the mutation named below; its scene:

contrary exception derives negation

Arxo Law

test "contrary exception derives negation" {
    given {
        context {
            legal_time @2026-09-13;
            decision_time @2026-09-13T09:00:00Z;
            knowledge_time @2026-09-13T09:00:00Z;
            timezone "UTC";
        }
        assert accused(entity_ref("urn:recipe:d-evidence:01:p")); assert convicted(entity_ref("urn:recipe:d-evidence:01:p"));
    }
    evaluate truth(innocent(entity_ref("urn:recipe:d-evidence:01:p")));
    expect truth_status == FALSE_ONLY;
    expect evaluation_status == COMPUTED;

}

Python

>>> import runpy
>>> check = runpy.run_path("docs/recipes/d-evidence/resources/check.py")
>>> check["check_variant"](https://github.com/arxohq/law/blob/master/docs/recipes/d-evidence/1)
'Д1: контрфактуал подтверждён; lawc = lawref'

Python

>>> import runpy
>>> check = runpy.run_path("docs/recipes/d-evidence/resources/check.py")
>>> check["check_expansion"](https://github.com/arxohq/law/blob/master/docs/recipes/d-evidence/1)
'Д1: expand показывает два правила; приоритет блокирующей оговорки отсутствует'

Counterfactual

Diagnostic mutation (check) — LDC-E0201.

Original fragment:

Output

presume innocent(p);

Replacement:

Output

presume innocent(p); scope accused(p);

The paired scenes above pin the change of outcome.

Boundary

The expansion is checked with the ordinary expand command: the rule and the defeater are visible; the absence of the prescribed priority is named below. This is not a definition of a criminal standard.

Counterfactual mutation: unless convicted(p); → unless convicted(p) then not innocent(p);.

For the blocking form, expansion shows the defeasible rule and the defeater, but no separate priority node; the blocking outcomes shown above are still correct.

Pitfall

Do not read a blocking proviso as asserting the opposite: it only lifts the presumption. Only a contrary proviso with an explicit then not innocent(p) establishes the negation.