Open Arsenal

No Unchecked Citations. No Hidden Conflicts.

LexCrosscheck is an AGPL-3.0+ specification for a modular retrieval-augmented generation (RAG) system designed specifically for legal research, research synthesis, citation verification, case briefs, legal writing, and legal arguments. LexCrosscheck allows users to describe legal questions and situations in natural language while the system identifies relevant facts, legal issues, jurisdictions, and applicable areas of law. It can retrieve relevant federal, state, local, regulatory, administrative, and judicial authorities and assemble them into source-grounded legal research that can be reviewed and traced back to the underlying authority.

LexCrosscheck is built around a strict source-verification and citation-integrity architecture. Every substantive legal citation is required to identify its underlying authority and provide a direct source link whenever one is available, with the system attempting to test the destination before presenting it as verified. The system distinguishes primary authority from secondary sources, checks whether citations correspond to actual legal materials, identifies potentially outdated or superseded authorities, and maps legal claims to their supporting sources. This creates an auditable chain from the user’s question to retrieved authority, cited evidence, and generated analysis rather than relying on unsupported model knowledge.

A central feature of LexCrosscheck is its modular jurisdiction and legal-domain architecture. Federal law, state law, municipal ordinances, regulations, court rules, administrative decisions, and specialized areas of law can be maintained as separate modules that can be independently added, updated, versioned, and specialized for the needs of a particular case. The system can combine multiple jurisdiction and law-type modules when a matter crosses legal boundaries and can identify conflicts between federal, state, local, administrative, or other applicable authorities. When conflicting requirements or interpretations are detected, LexCrosscheck identifies the competing authorities, explains the nature of the conflict, assesses uncertainty, and flags the issue rather than silently choosing an answer.

LexCrosscheck is designed around a human-in-the-loop model in which AI performs retrieval, organization, comparison, synthesis, citation checking, conflict detection, risk assessment, and document preparation while humans retain control over consequential legal decisions. Case briefs, research memoranda, legal arguments, and other generated documentation can include supporting authorities, counterarguments, unresolved issues, jurisdictional conflicts, source-verification status, and a risk-level warning for each material disclosure. The system is designed around a simple principle: No Unchecked Citations. No Hidden Conflicts. LexCrosscheck does not replace human legal judgment; it provides a verifiable research and reasoning infrastructure that helps humans understand the authorities, conflicts, risks, and evidence underlying a legal issue before deciding how to proceed.

This specification is licensed under AGPL-3.0+ and is free to use with required Section 7 attribution. Attribution-free deployment is available through a Specification Branding License, with fees based on use and deployment scope.