Extract and Validate Legal Citations using AI Document Analysis - n8n Workflow

• Legal professionals (paralegals, associates) needing to quickly audit sources in long legal documents.


• Researchers or academics automating the extraction of citation networks and primary sources.


• Users looking for advanced examples of structured data extraction using AI within an n8n workflow environment.


• Anyone seeking robust n8n templates for document analysis and validation.

Analyzing complex legal documents for citation accuracy and context can be tedious and time-consuming. This highly specialized n8n workflow solves this problem by integrating a powerful AI document processing tool, the PDF Vector n8n node, to handle the heavy lifting of extraction and structuring. Starting with a document from Google Drive, the n8n workflow uses the PDF Vector n8n node to identify various citation types (case law, statutes, academic papers, regulations) and capture crucial metadata, including the surrounding context and page numbers. The subsequent steps use custom JavaScript logic within a dedicated n8n node to validate citations (checking for missing reporters or section numbers), categorize primary and secondary authorities, and even fetch supplementary data for academic DOIs. The final output is a detailed Markdown report, providing not just the extracted list, but a comprehensive analysis of the document’s source materials. This n8n template showcases advanced capabilities for technical data processing.

This specialized n8n workflow starts with the Manual Trigger n8n node, which initiates the process upon receiving a Google Drive fileId.

1. Retrieve Document: The Google Drive n8n node downloads the target legal document (PDF or image) using the provided fileId.


2. AI Extraction: The workflow passes the binary file to the PDF Vector - Extract Citations n8n node. This crucial n8n node uses a detailed JSON schema and OCR capabilities to strictly extract structured citation data, including context and page numbers, essential for legal accuracy.


3. Validation & Analysis: The Analyze & Validate Citations Code n8n node then takes the structured AI output. It processes the lists, performs validation checks (e.g., ensuring case citations have volume/reporter/page), calculates totals for different citation types, and extracts all discovered DOIs for academic papers.


4. Conditional Fetching: The Has Academic DOIs? IF n8n node checks if any DOIs were extracted. If the list is not empty, the workflow proceeds down the true branch.


5. Fetch Academic Data (Optional): If DOIs exist, the PDF Vector - Fetch Papers n8n node retrieves metadata like abstracts, total citation counts, and PDF URLs for those academic sources, enriching the final data.


6. Report Generation: The Generate Citation Report Code n8n node synthesizes all data—the original extracted citations, validation warnings, analysis summaries, and newly fetched academic details—into a comprehensive Markdown report.


7. Export: Finally, the Save Citation Report n8n node writes the generated Markdown report to a file, completing the n8n automation cycle.

To deploy and utilize this n8n workflow, follow these steps:

1. Import the n8n template: Copy the provided JSON and paste it directly into your n8n instance via the 'New' menu > 'Import from JSON'.


2. Configure Credentials:

1. Test the n8n workflow: Execute the Manual Trigger n8n node, providing the fileId of a legal document (like a court opinion or statute) stored in your Google Drive. The n8n workflow will process the document and save the resulting Markdown report.

Manual Trigger (n8n trigger): Starts the workflow and accepts the fileId of the legal document to be analyzed.
Google Drive - Get Legal Document (n8n node): Downloads the specified document using an expression to pull the fileId from the preceding n8n trigger data. Operation is set to download.
PDF Vector - Extract Citations (n8n node): The core AI extraction step.
Function: Extracts structured data (case, statute, academic citations) from the document using OCR and AI.
Key Configuration: Uses a highly detailed prompt targeting legal content and a strict JSON schema to ensure predictable, structured output.
Analyze & Validate Citations (Code n8n node):
Function: Performs custom JavaScript logic to summarize citation totals, validate completeness of citation elements (e.g., ensuring case law has reporter information), and extracts DOIs.
Key Configuration: Creates data arrays for invalidCitations and academicDOIs used by downstream nodes.
Has Academic DOIs? (IF n8n node): Controls the flow. It checks if the doisToFetch variable (generated by the previous Code n8n node) is populated, ensuring the academic fetching process only runs when necessary.
PDF Vector - Fetch Papers (n8n node):
Function: Uses the extracted DOIs to retrieve additional metadata (like citation counts and PDF links) for secondary academic sources.
Key Configuration: Resource is set to academic and operation is fetch.
Generate Citation Report (Code n8n node):
Function: Merges all results from the extraction, validation, and academic fetching steps to construct a final, comprehensive Markdown analysis report.
Key Configuration: Builds sections for Case Law, Statutes, Academic Citations, and Validation Issues.
Save Citation Report (n8n node): Writes the final Markdown report content (from the previous n8n node) to a file named dynamically with the current date and time.