LexCrosscheck Specification

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LexCrosscheck

No Unchecked Citations. No Hidden Conflicts.

LexCrosscheck is a modular retrieval-augmented generation specification for legal research, legal research synthesis, citation verification, jurisdictional analysis, case briefs, legal writing, and legal arguments. It is designed to retrieve authoritative legal sources, verify citations and source links, identify conflicts between jurisdictions and authorities, assess research risks, and keep humans in control of consequential legal decisions.

Purpose

LexCrosscheck provides an architecture for building source-grounded legal research systems that can understand natural language legal questions and identify the laws, regulations, court decisions, rules, and other authorities relevant to a matter.

LexCrosscheck must distinguish retrieved legal authority from AI-generated analysis and human-selected legal positions. It must not present unsupported legal conclusions as authoritative law.

Core Principles

Source-grounded legal research
Mandatory citation for substantive legal claims
Direct source links whenever publicly available
Citation and source verification before presentation
Jurisdiction-aware retrieval and analysis
Modular legal-domain and jurisdiction architecture
Detection and disclosure of conflicting authorities
Temporal awareness of legal authority
Counterargument and adverse-authority research
Visible risk and uncertainty warnings
Human-in-the-loop decision making
Complete research auditability
No fabricated authorities, citations, quotations, or URLs
Vendor-neutral and model-neutral architecture
Extensible module and plugin system
Separation of legal authority, AI analysis, and human judgment

Natural Language Legal Intake Module

The Natural Language Legal Intake Module must accept legal questions, factual descriptions, documents, and other natural language inputs.

The module must identify and structure:

Legal questions
Potential legal issues
Relevant facts
Parties and entities
Locations
Dates and relevant time periods
Transactions and events
Property
Courts and government agencies
Claims and defenses
Rights and obligations
Potential remedies
Relevant areas of law
Potentially applicable jurisdictions
Missing or disputed facts
User-provided facts
Retrieved facts
AI inferences
Assumptions
Unknown information

The module must clearly distinguish facts supplied by the user from facts retrieved from legal sources and conclusions generated by the system.

Jurisdiction Identification Module

The Jurisdiction Identification Module must determine which jurisdictions may be relevant to a legal matter.

It must consider:

Federal jurisdiction
State jurisdiction
County jurisdiction
Municipal jurisdiction
Township jurisdiction
City jurisdiction
Local administrative jurisdiction
Tribal jurisdiction
Territorial jurisdiction
Trial courts
Appellate courts
Specialized courts
Administrative bodies

The module should consider physical location, residence, property location, place of transaction, place of conduct, choice-of-law provisions, forum-selection provisions, subject-matter jurisdiction, personal jurisdiction, procedural posture, and other jurisdictional factors.

The module must identify potentially relevant jurisdictions before conducting jurisdiction-sensitive legal research.

Jurisdiction Law Modules

LexCrosscheck must support independently maintained jurisdiction-specific law modules.

Each module must be independently installable, updateable, versioned, audited, enabled, disabled, and replaced.

Jurisdiction modules may include:

Federal Law
Federal Regulations
United States Supreme Court Authority
Federal Appellate Authority
Federal District Court Authority
State Law
State Regulations
State Court Authority
County Ordinances
Municipal Ordinances
Township Ordinances
Local Court Rules
Administrative Law
Tribal Law
Territorial Law
Specialized Court Authority

Each jurisdiction module must maintain metadata including jurisdiction, authority level, legal domain, source providers, source URLs, retrieval methods, update status, effective dates, repeal or amendment information, citation format, precedential status, geographic applicability, and temporal applicability.

Legal Domain Modules

LexCrosscheck must support separate modules for different areas of law so research can be specialized to the legal issues presented.

Supported domains may include:

Contract Law
Property Law
Real Estate Law
Landlord-Tenant Law
Tort Law
Criminal Law
Civil Procedure
Criminal Procedure
Family Law
Employment Law
Labor Law
Tax Law
Bankruptcy Law
Patent Law
Trademark Law
Copyright Law
Environmental Law
Administrative Law
Constitutional Law
Corporate Law
Securities Law
Consumer Law
Insurance Law
Privacy and Data Protection Law
Municipal Law
Election Law
Immigration Law
Health Law
Education Law
Estate and Probate Law

Legal domain modules must be able to work independently or in combination with jurisdiction modules.

Retrieval Module

The Retrieval Module must locate relevant legal authorities based on the structured legal question and identified jurisdictions.

Supported retrieval methods should include:

Keyword retrieval
Semantic retrieval
Hybrid retrieval
Citation retrieval
Case-name retrieval
Statute retrieval
Regulation retrieval
Docket retrieval
Boolean retrieval
Phrase retrieval
Date filtering
Court filtering
Jurisdiction filtering
Authority-level filtering
Legal-domain filtering

Retrieval must prioritize relevance while preserving source identity and authority metadata.

Source Authority Module

The Source Authority Module must classify retrieved materials according to their legal authority.

It must distinguish between:

Primary authority
Secondary authority
Binding authority
Persuasive authority
Nonbinding authority
Government guidance
Commentary
User-provided materials

Primary authority must be preferred when primary authority is required. A secondary source must never be silently substituted for the underlying primary authority.

Source Verification Module

The Source Verification Module must verify each substantive legal source before the system presents it as verified.

Verification should include:

Source existence
Source identity
Citation accuracy
Jurisdiction
Court or issuing authority
Authority type
Publication information
Effective date
Repeal status
Amendment status
Precedential status
Current validity
Source URL
Direct accessibility

The system must attempt to access a cited source before labeling its link as verified.

If verification cannot be completed, the system must clearly identify the source as unverified or inaccessible.

The system must never fabricate a source or URL.

Citation Validation Module

The Citation Validation Module must verify that citations are accurate and correspond to the legal authority they are intended to support.

Validation must consider:

Citation format
Case name
Court
Date
Reporter information
Docket number
Statute
Regulation
Section
Subsection
Source URL
Jurisdiction
Authority type

The module must flag or reject citations that cannot be verified.

Direct-Link Verification Module

Every substantive legal authority cited by LexCrosscheck must include a direct public source link whenever a public source is available.

The system must test the destination before identifying the link as verified.

Links must be categorized according to verification status, including:

Verified direct source
Verified landing page
Redirected source
Inaccessible source
Unverified source
Broken source

Official government and court sources should be preferred.

The system must never invent a replacement URL when the original source cannot be located.

Citation Integrity Module

The Citation Integrity Module must evaluate the relationship between legal claims and their supporting authorities.

It must identify:

Unsupported claims
Incorrect citations
Authority mismatches
Overbroad interpretations
Misquoted authority
Out-of-context authority
Superseded authority
Overruled authority
Repealed law
Wrong jurisdiction
Wrong court
Wrong date
Wrong statutory section
Incorrect procedural history

Every material legal claim should be traceable to the authority supporting it.

Evidence-to-Claim Mapping Module

LexCrosscheck must maintain an evidence chain connecting legal conclusions to their supporting sources.

The minimum relationship must be:

Claim → Authority → Exact Source Location → Verification Status

The system should preserve the relevant quotation, passage, section, paragraph, page, or other source location when available.

Legal Research Module

The Legal Research Module must transform natural language legal questions into structured research plans.

A research plan may include:

Legal issues
Relevant doctrines
Search terms
Applicable jurisdictions
Relevant legal domains
Primary authorities
Secondary authorities
Procedural rules
Conflicting authorities
Adverse authority
Missing facts
Research gaps
Retrieval confidence
Legal uncertainty

The module must conduct research across all relevant jurisdiction and legal-domain modules.

Research Synthesis Module

The Research Synthesis Module must organize retrieved authorities into a coherent legal research analysis.

It must distinguish among:

Controlling authority
Binding authority
Persuasive authority
Nonbinding authority
Secondary authority
Conflicting authority
Uncertain authority

The module must not collapse conflicting authorities into a single unsupported conclusion.

Jurisdiction Conflict Detection Module

The Jurisdiction Conflict Detection Module must identify conflicts between legal authorities from different jurisdictions or levels of government.

Potential conflicts include differences involving:

Statutory requirements
Definitions
Deadlines
Procedures
Legal standards
Elements of claims
Defenses
Remedies
Damages
Regulatory requirements
Privacy obligations
Tax obligations
Contract requirements
Precedent

When a conflict is detected, the system must identify:

The jurisdictions involved
The competing authorities
The nature of the conflict
Authority level
Geographic scope
Temporal scope
Potential controlling authority
Potential resolution mechanisms
Remaining uncertainty

Material conflicts must not be silently resolved by the AI.

Federal-State Conflict Module

The Federal-State Conflict Module must analyze potential conflicts between federal and state authority.

It should evaluate:

Express preemption
Implied preemption
Conflict preemption
Field preemption
Supremacy Clause considerations
Savings provisions
Concurrent authority
Federalism considerations

The module must distinguish between an actual legal conflict and authorities that merely appear different because they regulate different issues.

Conflict Resolution Module

The Conflict Resolution Module must organize competing authorities according to relevant legal principles.

Potential considerations include:

Authority hierarchy
Jurisdiction
Subject matter
Geographic applicability
Temporal applicability
Preemption
Precedent
Statutory construction
Regulatory authority
Choice-of-law provisions
Forum-selection provisions

The module must present competing interpretations and identify the factors that may determine which authority controls.

A material conflict must produce a human decision gate rather than an automatically imposed legal position.

Temporal Law Module

The Temporal Law Module must determine which version of a legal authority applies to the relevant date.

It must track:

Enactment date
Effective date
Amendment date
Repeal date
Sunset provisions
Historical versions
Prospective application
Retroactive application
Transitional provisions

The system must not apply current law automatically when historical law is required.

Precedent and Legal Treatment Module

The Precedent and Legal Treatment Module must track the treatment of judicial authorities.

It should identify:

Cited-by relationships
Negative treatment
Overruling
Reversal
Vacatur
Distinguishing
Adoption
Affirmance
Subsequent interpretation

A search result or citation relationship must not automatically be treated as evidence that a case remains controlling.

Counterargument Module

The Counterargument Module must actively search for authorities and facts that weaken or contradict the proposed analysis.

It should identify:

Contrary precedent
Contrary statutes
Contrary regulations
Adverse interpretations
Negative treatment
Distinguishing facts
Procedural obstacles
Jurisdictional objections
Alternative legal theories

The system must not suppress adverse authority merely because it conflicts with the preferred conclusion.

Case Brief Module

The Case Brief Module must generate structured case briefs containing, when available:

Case name
Court
Date
Citation
Docket number
Procedural history
Facts
Legal issues
Rule
Holding
Reasoning
Disposition
Concurring opinions
Dissenting opinions
Subsequent treatment
Cited authorities
Citing authorities
Precedential status

Every material statement in a case brief must be traceable to the underlying source.

Legal Writing Module

The Legal Writing Module must support generation of:

Legal memoranda
Motions
Briefs
Legal letters
Regulatory comments
Legal research reports
Internal legal analysis
Legal outlines
Other structured legal documents

Generated legal writing must preserve source citations and identify unsupported propositions.

A citation audit must occur before a document is presented as complete.

Legal Argument Module

The Legal Argument Module must structure legal arguments around:

Legal proposition
Supporting authority
Relevant facts
Application of law to facts
Counterarguments
Responses
Conflicting authority
Risk
Uncertainty
Missing facts

The module must distinguish between established authority and an argument or interpretation generated by the system.

Risk Assessment Module

The Risk Assessment Module must assign visible risk warnings to material legal disclosures.

Risk levels must include:

Low
Moderate
High
Critical

Risk assessments must identify the reasons for the assigned level.

Risk may be increased by:

Unverified authority
Conflicting jurisdictions
Missing facts
Uncertain precedent
Outdated sources
Ambiguous law
Material adverse authority
Weak source support
Significant procedural uncertainty
Potentially irreversible consequences

Risk warnings must not be hidden from the user.

Source Freshness Module

The Source Freshness Module must track the currency of legal sources.

It should maintain:

Retrieval date
Verification date
Publication date
Effective date
Modification date
Repeal date
Last source check
Revalidation status

High-value legal authorities should be revalidated when necessary before being relied upon in new research.

Uncertainty Module

LexCrosscheck must explicitly represent uncertainty.

Uncertainty may arise from:

Missing facts
Ambiguous language
Conflicting authority
Incomplete source access
Uncertain precedent
Historical law
Jurisdictional ambiguity
Incomplete retrieval
Conflicting interpretations
Insufficient authority

The system must not convert uncertainty into certainty merely to produce a definitive response.

Retrieval Confidence and Legal Certainty

LexCrosscheck must keep retrieval confidence separate from legal certainty.

A highly relevant search result does not establish that a legal proposition is correct.

The system must distinguish:

Retrieval Confidence: Confidence that the retrieved source is relevant to the research question.

Legal Certainty: Confidence that the legal proposition is supported by applicable authority after considering jurisdiction, authority hierarchy, temporal applicability, precedent, conflicting authorities, and available facts.

Research Audit Trail Module

The Research Audit Trail Module must preserve the history of legal research and analysis.

The audit trail should include:

Original question
Normalized question
User-provided facts
Identified jurisdictions
Legal domains
Search queries
Retrieved sources
Source versions
Source verification results
Citations
Conflicts
Risk assessments
AI-generated analysis
Human decisions
Final output

The audit trail must allow a reviewer to reconstruct how the system reached its research output.

Human-in-the-Loop Governance Module

LexCrosscheck must maintain human control over consequential legal decisions.

The AI must not:

Decide which conflicting jurisdiction controls without human authorization
Represent itself as a lawyer
Make irreversible legal decisions on behalf of a user
Override human judgment
Suppress adverse authority
Remove material risk warnings
Mark an unverified citation as verified
Convert uncertainty into certainty
Present an AI interpretation as binding law

Human reviewers must be able to:

Accept or reject authorities
Add sources
Reject interpretations
Modify factual assumptions
Select or reject jurisdictions
Approve or reject arguments
Request additional research
Resolve identified conflicts
Approve final documentation

Material human decisions should be recorded in the audit trail.

Human Decision Gate

When LexCrosscheck identifies a material legal conflict, significant uncertainty, or consequential decision, it must provide a Human Decision Gate.

The gate should present:

Legal issue
Relevant jurisdictions
Competing authorities
Conflict description
AI analysis
Risk level
Uncertainty
Missing information
Recommended additional research
Available decision options

The system must pause or clearly defer the consequential decision until the human reviewer determines how to proceed.

Source Priority Module

LexCrosscheck should prioritize sources in the following order:

Official court sources
Official legislative sources
Official government sources
Official regulatory or administrative sources
Verified public legal repositories
Secondary legal databases
Legal commentary

Higher-priority sources should be preferred when multiple sources contain substantially equivalent authority.

Source Failure Handling Module

When a source cannot be accessed or verified, LexCrosscheck must:

Report the failure
Preserve the original citation
Identify the verification status
Attempt an authoritative alternative source when appropriate
Distinguish the alternative source from the original source
Never fabricate a replacement citation or URL

Hallucination Prevention Module

LexCrosscheck must prevent the generation of fabricated:

Cases
Statutes
Regulations
Court decisions
Dockets
Courts
Judges
Legal doctrines
Citations
URLs
Quotations
Holdings
Procedural histories
Legal requirements

When a requested authority cannot be verified, the system must state that it could not verify the authority.

Risk and Disclosure Module

Every substantive legal disclosure must expose relevant:

Source status
Citation status
Verification status
Risk level
Jurisdiction
Authority level
Legal uncertainty
Conflicting authority
Missing information

The system must not conceal material limitations from the user.

Security and Privacy Module

LexCrosscheck must support protection of confidential legal information.

Security capabilities should include:

Local processing where available
Encryption
Access controls
Authentication
Authorization
Audit logging
Data minimization
Retention controls
Tenant isolation
Confidential document handling

The system should minimize the collection, transmission, and retention of sensitive legal information.

Documentation Generation Module

LexCrosscheck must support generation of structured research documentation, including:

Legal research reports
Case briefs
Legal memoranda
Citation tables
Authority tables
Jurisdiction maps
Conflict reports
Risk reports
Argument matrices
Counterargument reports
Source verification reports
Research audit logs

Generated documents must preserve citations, source links, verification status, risks, conflicts, and unresolved questions where applicable.

Export and Review Module

Final exports must remain subject to human review.

A final legal research document should be capable of including:

Legal analysis
Supporting authorities
Citations
Direct source links
Source verification status
Risk warnings
Jurisdictional conflicts
Counterarguments
Unresolved questions
Missing facts
Human decisions
AI-generated content disclosures

Interoperability Module

LexCrosscheck must support interoperability between jurisdiction modules, legal-domain modules, retrieval systems, source registries, verification systems, document generators, and optional plugins.

Modules should communicate through defined interfaces so individual components can be replaced or upgraded without requiring the entire system to be redesigned.

Plugin Architecture

LexCrosscheck must support optional plugins that extend functionality without making those capabilities mandatory to the core specification.

Plugins may provide:

Additional legal jurisdictions
Additional legal domains
Specialized court databases
Additional source repositories
Legal citation formats
Document formats
Source monitoring
Docket monitoring
Legislative tracking
Regulatory tracking
Case-law treatment analysis
Advanced conflict analysis
Specialized legal research workflows
Translation
Document comparison
Legal document ingestion
External verification services
Human review workflows
Organization-specific research policies

Optional plugins must identify their capabilities, supported jurisdictions, supported authority types, source dependencies, verification capabilities, version, and limitations.

Plugins must not bypass core citation, verification, conflict disclosure, risk, or human-governance requirements.

Plugin Verification Requirements

Optional plugins that provide legal sources or legal analysis must identify the origin and authority level of their data.

Plugins must not cause unverified material to be represented as verified.

Plugin-generated legal content remains subject to the same citation, source verification, conflict detection, risk assessment, and human review requirements as core system output.

Minimum Output Contract

A compliant LexCrosscheck research response must provide, when applicable:

Legal question
Relevant facts
Applicable jurisdictions
Relevant legal domains
Legal analysis
Supporting authorities
Citations
Direct source links
Citation verification status
Source verification status
Conflicting authorities
Counterarguments
Risk level
Uncertainty
Missing facts
Human decision points

The system must not omit material conflicts or verification failures merely to produce a cleaner response.

Example Research Flow

A typical LexCrosscheck workflow should:

Receive a natural language legal question
Identify relevant facts and missing information
Identify potentially applicable jurisdictions
Identify relevant legal domains
Activate appropriate jurisdiction and legal-domain modules
Generate a structured research plan
Retrieve primary and secondary authorities
Verify source identity and accessibility
Validate citations
Determine temporal applicability
Evaluate precedential treatment
Search for adverse authorities and counterarguments
Detect jurisdictional conflicts
Assess risk and uncertainty
Generate source-grounded analysis
Present citations and tested source links
Present conflicts and risks
Request human decisions where required
Generate the requested legal documentation
Preserve the research audit trail

Example Conflict Output

When authorities conflict, the system should identify:

Issue: The legal requirement under review.

Jurisdiction A: Applicable authority and source.

Jurisdiction B: Conflicting authority and source.

Conflict: Specific difference between the authorities.

Authority Level: Relative authority of each source.

Temporal Scope: Relevant effective dates and historical versions.

Geographic Scope: Where each authority applies.

Potential Resolution: Applicable principles such as preemption, hierarchy, precedent, or choice of law.

Risk: Current risk level and reasons.

Human Decision: The decision that requires human review.

Specification Branding License (SBL)

Standard

Fully AGPL-3.0+ compliant system
Copyleft enforced for network deployments
Required attribution:
- Roxanne Ardary
- https://www.roxanneardary.com/

Optional

Specification Branding License (SBL)
- Attribution-free commercial deployment
- Pricing based on scale, usage, and deployment scope
- https://roxanneardary.com/lexcrosscheck/

License & Notice Requirements

LexCrosscheck is released under the GNU Affero General Public License v3.0 or later (AGPL-3.0+).

By contributing to any Open Arsenal project, you agree that your contributions will also be released under this license.

Please note the following:

All contributions must comply with the AGPL-3.0+ terms.
Under Section 7 of the license, all redistributions, forks, and derivative works must preserve attribution to:
Roxanne Ardary and roxanneardary.com.
LexCrosscheck specifications are free to use with attribution. A Specification Branding License can be negotiated upon request.
The project’s notice.md file tracks attribution requirements and contributor acknowledgments. Any update that adds new contributors or modifies attribution should also update notice.md.
When submitting a pull request, ensure that any new files maintain the attribution headers where applicable.
Network-deployed versions of this software must also remain fully AGPL-3.0+ compliant, including exposure of source code modifications when applicable under the license.

For full legal details, please refer to the AGPL-3.0+ license and the project’s notice.md file.

Notice – LexCrosscheck

Attribution Requirement: Under Section 7 of the AGPL 3.0+ license, all redistributions, forks, and derivative works, including network-deployed versions of this project, must provide attribution to Roxanne Ardary and roxanneardary.com.

Contributors

This file tracks contributors and their specific contributions to the project.

Roxanne Ardary, roxanneardary.com – September 2, 2026
Created the repository for LexCrosscheck. Developed the specification for a modular AI-powered legal research and retrieval system featuring verified citations, jurisdictional conflict detection, source-grounded legal analysis, case briefs, legal writing, and human oversight.
[Add other contributors here] – [Date]
[Describe contribution in one sentence]

License – LexCrosscheck

This repository is licensed under the GNU Affero General Public License v3.0 or later (AGPL-3.0+).

Key Points:

You are free to use, modify, and distribute the code.
All redistributions, forks, and derivative works or network-deployed versions must also be licensed under AGPL-3.0+ and provide attribution to Roxanne Ardary and roxanneardary.com as required under Section 7 of the license.
The software is provided “as is,” without warranty of any kind.

For the full license text, see GNU AGPL-3.0 License.