The Evolution of Evidence: From Testimony to System-Generated Data

The Evolution of Evidence: From Testimony to System-Generated Data

This is the first article of a 10-part series on how technology is transforming evidence, litigation, and dispute resolution. In this first installment, we’ll explore how evidence has changed over time, leading us to the rise of System-Generated Data (SGD) and its impact on the future of litigation.

For centuries, legal disputes relied almost exclusively on testimonial and physical evidence. Courts depended on witnesses to recount events and on tangible objects like contracts, weapons, or property to support their claims. This method had inherent limitations—human memory is fallible, physical evidence can degrade, and bias often plays a role in shaping narratives.

Over time, we saw that the introduction of documentary evidence—written contracts, business records, and later emails and digital documents—improved reliability. Courts increasingly recognized that documents could preserve an account of events far more accurately than human recollection. However, even written evidence depended on testimony to establish its origins and authenticity.

Today, we are witnessing another paradigm shift, one that is as disruptive as the move from oral testimony to written records: the rise of digital and transactional evidence. Contrary to what you might expect, this is not email, text messages, and social media. It is largely non-textual data. I call this System-Generated Data (SGD)— and this new category of evidence is fundamentally changing how facts are established in legal disputes.

What Is System-Generated Data (SGD)?

SGD refers to data automatically created and logged by digital systems, independent of human input. Unlike traditional documents that require a human to write, edit, and store them, SGD is generated passively by machines and algorithms. Examples include:

• Mobile device location logs: Tracking user movements with GPS and cell tower data
• Internet of Things (IoT) sensor data: Smart home devices, wearable fitness trackers, or connected car logs
• Industrial Internet of Things (IIoT) sensor data: devices that track weather, the electrical grid, pipelines, manufacturing, shipping, and more.
• Financial transaction logs: Automated banking records, cryptocurrency transactions, and payment confirmations
• Email and communication metadata: Records of when a message was sent, received, and read
• Autonomous vehicle telemetry: Sensor data from self-driving cars documenting acceleration, braking, and environmental factors

What makes SGD distinct from previous forms of evidence is its objectivity and granularity. It doesn’t rely on human memory or bias. Instead, it provides a machine-recorded, time-stamped, and structured representation of events. In many cases, it tells us what actually happened—often with more precision than a human witness ever could.

How SGD is Transforming Litigation

The rise of SGD is reshaping legal investigations, case strategy, and court proceedings in several key ways:

1. Replacing Human Testimony with Digital Trails

Juries have traditionally been tasked with evaluating the credibility of witnesses—determining who seems more believable. But with SGD, the focus shifts. Instead of two drivers testifying about a car accident, their vehicle telematics and GPS logs may provide an objective reconstruction of the crash.

2. More Facts, Fewer Inferences

SGD reduces the need for juries and judges to fill in gaps with assumptions and inferences. With surveillance footage, location data, and timestamped logs, courts can reconstruct events in ways that were previously impossible. And this data is often generated on a frequency basis that approaches constant and pervasive. The burden of interpretation shifts from human testimony to data analytics and expert witnesses.

3. Changing the Role of the Expert Witness

In an SGD-driven world, expert witnesses will play an even larger role—not just in analyzing data, but in translating complex digital evidence for juries and judges. For example, an AI algorithm flagging financial fraud must be explained in a way that makes sense to non-technical decision-makers.

4. Authentication and the “Proof-of-Origin” Challenge

The rise of SGD introduces new challenges in authentication and admissibility. When dealing with physical evidence, maintaining an unaltered state after acquisition is a key concern, known as the “chain of custody.” 

In contrast, digital evidence can be digitally hashed, allowing its integrity to be easily verified later, making the traditional chain of custody less critical. However, understanding the origin of digital evidence before it comes under our control is becoming increasingly important—and more feasible. Looking ahead, courts may need to adopt “proof-of-origin” standards when evaluating authenticity and admissibility.

Preparing for the Future of Evidence

As the legal system adapts to the growing presence of SGD, litigators and investigators should:

• Understand what types of digital evidence exist and how they are stored.
• Work with experts who can authenticate and interpret digital trails.
• Develop courtroom strategies that leverage SGD effectively while explaining it to judges and juries.

The shift from oral testimony to documentary evidence reshaped the legal world once before. We are now at the threshold of a similar revolution—one in which data, not words, may become the primary storyteller in the courtroom.

Closing Thoughts: Join the Conversation

This is just one piece of the bigger conversation on the future of evidence. As legal professionals, we are relied upon to stay ahead of how emerging technologies impact investigations, case strategy, and courtroom advocacy. It’s important to partner with people who specialize in helping law firms, corporations, and regulators navigate the challenges of digital evidence—whether it’s mobile forensics, AI-generated data, or system logs that rewrite how we establish facts. Let’s continue the discussion.