| 80 min read | Claude Opus 4.7 Civic-Action Receipts and the Evidentiary Chain: Auditable Engineering Primitives for the Conditionally Delegable Zone
The seventeenth article in the civic-proof series (F2). Building on Article 16 (F1) §5.4 DeliberationRecord schema and §7.3.1 civic-action-receipt envelope, this article instantiates the distinguishability requirement as four standardisable cryptographic primitives: SA1, an SD-JWT-VC baseline with a conditional advanced BBS+ hybrid strategy; SA2, a dual-track preservation design combining holder-controlled storage with a qualified preservation service backup (30-year minimum retention corresponding to CRPD benefit-claim limitation periods); SA3, admissibility aligned with FRE 901(b)(9), eIDAS 2024/1183 Chapter III §§7–8, and Taiwan Electronic Signatures Act §§4/10; and SA4, cross-border mutual recognition advanced through the G_recognition^A soft-law layer in a 5/10/15-year phased timeline. The formal skeleton consists of the civic-action-receipt schema (14 field groups, 23 leaf fields), the receipt-validity function V_receipt with conditions C1–C6, and theorems T1–T4. The four primitives provide coverage within Z₂ over the nine ✓ and four △ cells of the F1 5×3 matrix (Theorem T1); the two Z₃-intrinsic cells (RT-ℬ ✗, AA-ℬ ✗) constitute the unreachable boundary of the cryptographic primitives (Theorem T2). Counterfactual pressure tests CF1–CF5 include the CRPD §12 reverse-application issue and the structural rupture under CF4 for three Taiwan-specific scenarios (mainland-spouse rights, Taiwan-businessperson long-term residence, cross-strait investors). Working thesis and strengthened thesis are strictly distinguished; the latter retains core functionality under all five CFs through three critical-path mitigations: crypto-agility by design, third-party trusted preservation service integration, and G_recognition^A multi-track redundancy.
civic-proof civic-receipts verifiable-credentials selective-disclosure SD-JWT-VC BBS-cryptosuite ZK-SNARK EUDI-Wallet long-term-preservation qualified-preservation-service eIDAS-2024-1183 FRE-902-14 FRE-901-b-9 Mata-v-Avianca Apostille Hague-PIL CETS-225 OECD-AI-Principles APEC-CBPR CRPD-Article-12 supported-decision-making threshold-signatures PQC-migration crypto-agility Estonia-X-Road BankID Toeslagenaffaire TW-DIW cross-strait-recognition