How to Handle Complex Emerging Data Sources for eDiscovery

Legal discovery is being reshaped by the rise of emerging data sources, with profound implications for litigation, compliance, and investigations. Complex Discovery’s Rob Robinson reports on a 2025 LegalTechTalk Conference panel focused on how to handle these challenges. 

Moderated by Tom Makin of Simmons & Simmons, the panel featured industry leaders Christina Zachariasen of A&O Shearman, Jeffrey Shapiro of EY, and Michael Sarlo of HaystackID. They explored how workflows and governance strategies must be adapted to handle emerging electronically stored information, including ephemeral messages, chats, multimedia, and outputs from generative artificial intelligence (GenAI). 

Panelists highlighted the value of involving experts early, integrating AI, and implementing a risk-aware governance framework. Zachariasen pointed to the rapid growth of messaging data, which has surpassed email in many document collections, noting the need for early involvement of technical experts as platforms like Slack and Teams are producing increasingly complex datasets. 

Sarlo emphasized the importance of understanding platform usage and user interactions, as collaborative environments often lack clear custodian boundaries: “We start to look at who is talking to whom and about the method to reduce volume early on.” Shapiro framed the conversation within the context of enterprise-wide governance, emphasizing compliance with frameworks such as the General Data Protection Regulation (GDPR) and the broader need for risk-aware information strategies.

Despite advances in technology, the panel acknowledged persistent gaps in integrating structured and unstructured data. Sarlo said this was an even bigger challenge in mobile and Slack data acquisition: “You need to go and check every single time if the acquisition method you use actually still works today.” 

With the increased use of emerging data sources, security and compliance risks have been heightened, particularly in cross-border transfers and breach responses. Zachariasen and Sarlo advocated for prompt third-party consultants and strong internal hygiene protocols.

The discussion concluded with a focus on AI’s expanding role in investigative workflows and streamlining reviews. According to Sarlo, “GenAI is most effective when used with intent and context. It doesn’t work as well if you don’t know what you want to find.”