Supporting Humans in Evaluating AI Summaries of Legal Depositions
Naghmeh Farzi, Laura Dietz, Dave D. Lewis
TL;DR
This work addresses the risk of factual inaccuracy in AI-generated legal deposition summaries by introducing nugget-based extraction and alignment to support end users. It presents a two-workflow HITL prototype: (1) guided comparison of two summaries to identify nugget-level differences, and (2) guided refinement of a single summary guided by nugget evidence and citation support. The approach combines automatic nugget banks, LLM-based nugget judgments, and citation verification to provide actionable guidance, enabling legal professionals to verify, compare, and improve summaries with reduced cognitive load. The long-term goal is to integrate structured nugget feedback into LLM responses, improving first-draft quality and extending the framework to other high-stakes domains.
Abstract
While large language models (LLMs) are increasingly used to summarize long documents, this trend poses significant challenges in the legal domain, where the factual accuracy of deposition summaries is crucial. Nugget-based methods have been shown to be extremely helpful for the automated evaluation of summarization approaches. In this work, we translate these methods to the user side and explore how nuggets could directly assist end users. Although prior systems have demonstrated the promise of nugget-based evaluation, its potential to support end users remains underexplored. Focusing on the legal domain, we present a prototype that leverages a factual nugget-based approach to support legal professionals in two concrete scenarios: (1) determining which of two summaries is better, and (2) manually improving an automatically generated summary.
