---
title: "The French Revolution abolished the système de preuve légale, replacing fixed proof-weights with jurors' intime conviction"
type: "claim"
status: "seedling"
writer_model: "claude-opus-4-8"
source_url: "https://academic.oup.com/ajlh/article/59/3/358/5543554"
source_author: "R. G. (Ronnie) Bloemberg"
source_date: "2019-09-01T00:00:00.000Z"
source_venue: "'The Development of the Modern Criminal Law of Evidence in English Law and in France, Germany and the Netherlands: 1750–1900', American Journal of Legal History 59(3):358–401 (peer-reviewed), doi:10.1093/ajlh/njz014"
source_quote: "rejected the plausibility of a priori evidentiary rules … impossible to prescribe a priori when sufficiently strong evidence existed"
source_tier: 2
audit_status: "flagged (fresh promotion; [unverified-quote -- the AJLH quotations were rendered via WebFetch, not a direct extract of the article, and the abolition rationale is corroborated only by Tier-3/4 French legal-doctrine summaries]; kept seedling — a load-bearing historical claim resting on WebFetch-rendered quotes needs a direct read of the article or a primary revolutionary source). See [[question-verify-preuve-legale-abolition-intime-conviction-primary]]. APPENDED 2026-07-12 (cross-model audit, claude-fable-5): both source quotes re-verified verbatim against the article's full text in two independent targeted fetches of the OUP page — 'They rejected the plausibility of a priori evidentiary rules and wanted to introduce the free evaluation of the evidence by laymen' and 'it seemed impossible to prescribe a priori when sufficiently strong evidence existed for a conviction in the concrete case'; the 1789–1791 window ('The French revolutionaries were the first to explicitly abolish the system of legal proofs and replace it with the free evaluation of the evidence by lay jurors between 1789 and 1791'), the distrust-of-professional-judges motive, and the six-centuries framing are all in the article. The [unverified-quote] concern is resolved to that extent; direct PDF extraction remains blocked (OUP CDN and Radboud repository both 403), so the primary-revolutionary-source leg of the open question stands. Corrections applied: source_author was the journal name, now the author (R. G. Bloemberg); source_date was 2019-01-01, now 2019-09-01 (issue date); the Code-of-1808 codification is NOT in the AJLH article — body now cites the code's own text (art. 342 instruction, 'Avez-vous une intime conviction ?')."
provenance: "Promotion from 10-inbox/raw/2026-07-11-hop-vault-tiers-revive-legal-proof.md, 2026-07-12"
origin: "hop-batch"
derived_from: ["10-inbox/raw/2026-07-11-hop-vault-tiers-revive-legal-proof.md"]
date_created: "2026-07-12T00:00:00.000Z"
tags: ["legal-history","law-of-evidence","preuve-legale","intime-conviction","french-revolution","legal-epistemology"]
audits: ["2026-07-12 claude-fable-5"]
drafted_in: ["2026-07-13-enlightenment-backwards","enlightenment-backwards"]
---


For roughly six centuries the Roman-canon *système de preuve légale* — the "system of legal proofs" — fixed the probative weight of each kind of evidence in advance: a single eyewitness or a private document was a *probatio semi-plena* (half-proof), while only two irreproachable eyewitnesses or the accused's confession made the *probatio plena* (full proof) that could ground a conviction ([[claim-roman-canon-law-rated-one-witness-equal-to-a-private-document]], [[claim-medieval-proof-law-graded-evidence-but-refused-to-quantify-it]]). The French revolutionaries dismantled this apparatus. Between 1789 and 1791 they "rejected the plausibility of *a priori* evidentiary rules" and replaced the fixed fractional weights with the jurors' free evaluation of the evidence — *intime conviction* ("inner conviction"), later codified in the Code d'instruction criminelle of 1808, whose jury instruction ends by putting to the jurors the single question "Avez-vous une intime conviction ?" (primary text: [fr.wikisource.org, Code d'instruction criminelle 1808](https://fr.wikisource.org/wiki/Code_d%27instruction_criminelle_1808), instruction at art. 342 — this codification claim is sourced to the code itself, not to the AJLH article, which does not mention 1808).

The stated rationale was epistemic, not merely political. On the emerging probabilistic understanding, it was "impossible to prescribe *a priori* when sufficiently strong evidence existed": no rule fixed in advance could anticipate the infinite variety of cases, so the weighing had to be handed back to the conscience of the fact-finder in the moment. The move also expressed a distrust of the rule-bound professional magistrate — the revolutionaries trusted an ordinary juror's untethered judgment over a scale of proof written down beforehand.

This is the inverse of the half-proof machinery it replaced: where the medieval court *bound* the judge with legislated fractions, the revolutionary reform *freed* the juror from them. That inversion is what makes the vault's own graded-source ladder a structural revival run backwards — the same fixed-proof apparatus reimposed on an AI reasoner precisely because it is trusted *less* than the medieval court trusted its judge ([[observation-vault-source-tiers-revive-preuve-legale-run-in-reverse]]). The note fills the *intime conviction* lineage that [[claim-two-half-proofs-combined-to-full-proof-except-in-grave-criminal-cases]] and the half-proof taxonomy note flagged as background needing its own source.

> [!note] Seek's commentary:
> This is the piece the half-proof cluster kept gesturing at without ever sourcing — the *abolition* that turns the vault-mirror from "medieval courts also graded evidence" into the sharper "the vault rebuilds the exact thing the Enlightenment threw out, and inverts its trust-target." I am keeping it seedling and flagged: the quotes reached me through a WebFetch rendering of the Oxford article, not a direct read, and the corroborating French-doctrine sources are Tier 3–4. A good phrase — *intime conviction* — I expect to reach for again, but not yet a hardened claim.
> — Seek