Rethinking the Chain of Custody: Proof of Origin and the Future of Digital Evidence

This is the fourth article of a 10-part series on how technology is transforming evidence, litigation, and dispute resolution. In this installment, we’ll explore how digital evidence can be faked or modified and explore the concepts of “chain of custody” and “proof of origin.” Other articles in the series can be found here.

A hush washed over the courtroom as the prosecutor held up a large manila envelope. The defense attorney watched closely as the envelope was opened, revealing a blood-stained handkerchief inside a plastic evidence bag. A label on the bag documented the journey of the evidence—each name, each date, each transfer from the crime scene to the evidence locker to the prosecution’s hands that morning. The “chain of custody” was intact. The evidence was authenticated. It was admitted.

A chain of custody protects physical evidence. Every person, every handoff, every storage location is manually recorded to ensure that the evidence remains untampered. A missing signature, a gap in the log, and the entire piece of evidence could be challenged or thrown out altogether.

But what if you could take any piece of evidence, today, and instantly prove that it was unmodified, unaltered, unchanged from the moment it was collected? That would alleviate the need for meticulous tracking, and the reliance on procedural paperwork.

Welcome to the world of digital evidence.

Integrity is Easy in the Digital World

Digital evidence (e.g., emails, videos, documents, hard drive images, etc.) doesn’t require a chain of custody the way physical evidence does. Instead, it has something far more precise: the digital hash value.

A digital hash value is a mathematical fingerprint of a file. When a file is created or collected, forensic software tools run a hashing algorithm (usually MD5, SHA-1, or SHA-256) to generate a fixed-length string of characters, unique to that exact file. If a single bit changes, the hash value changes.

It’s that simple.

A file’s integrity isn’t confirmed by tracking every hand that touched it. It’s confirmed by re-hashing it at any time and comparing it to the original hash. If the values match, the file hasn’t changed.

No paperwork. No signatures. No need to rely on memory or human process failures. Just math.

For this reason, these hashing algorithms are also part of Blockchain security.

So, What’s the New Challenge?

If proving the integrity of a digital file is now trivial, where do we need to focus our attention?

The real challenge and value is proving where it came from. Integrity is no longer the issue. Authenticity is.

In an era of deepfakes, altered documents, and synthetic media, we need more than just proof that a file hasn’t changed. We need “proof of origin”—a way to confirm not just that a file is intact, but that it is real.

Proof of Origin: The New Standard for Digital Evidence

Every digital artifact leaves a trail. Emails have headers. Documents have metadata. Photos and videos contain embedded timestamps, GPS locations, and device signatures. These digital breadcrumbs provide “proof of origin”—a way to trace a file back to its true source.

This is where forensic investigations are shifting. It’s no longer just about checking a file’s integrity. It’s about answering deeper questions:

• Where did this file come from?
• Who created it?
• Was it modified? If so, by whom and when?
• Is this video a genuine security recording, or was it generated by AI?

Example: Verifying a Video’s Authenticity

Imagine a criminal trial where the key evidence is a security camera video of a suspect at a crime scene.

The defense claims the footage is fake. Maybe it was altered. Maybe it was AI-generated. Maybe it was never recorded by the surveillance system at all.

A simple hash check won’t help. The defense isn’t arguing that the file has changed since it was collected—they’re arguing that it was never real to begin with.

That’s where proof of origin comes in. Investigators can:

1. Analyze metadata to confirm whether the file was actually recorded by the security system.
2. Check embedded device signatures to ensure it came from the correct camera model.
3. Cross-reference logs from the security system to see if the file matches recorded events.
4. Use forensic AI tools to detect frame inconsistencies or signs of digital manipulation.

With proof of origin, the focus shifts from proving that a file is unchanged to proving that it is genuine.

Why This Shift Matters

Forensic investigations, legal proceedings, and cybersecurity operations have relied on chain of custody for decades. But in a digital world, that model is becoming obsolete. At the same time, Deepfakes and AI-generated content are changing everything. A world where anyone can fabricate evidence means proof of origin is more important than ever.

Here’s why:

• Digital evidence is not a physical object. It can be copied perfectly, stored infinitely, and hashed at any time to confirm integrity.
• The burden of proof is shifting. Courts no longer just ask, “Was this file handled correctly?” They now ask, “Was this file ever real?”

What’s even more interesting is that principles behind “proof of origin” can be increasingly applied to any evidence—even physical evidence. Thanks to heavily automated and integrated supply chains and the integration of digital features, many physical items can be traced as if they were digital files. Similarly, direct testimony can now be tested in ways that were not available 20 years ago.

In short, virtually everything in the world is currently created by, controlled by, or recorded by computerized systems. And those data trails allow us to verify (or challenge) almost any object, event, or memory.

Where We Should Invest Our Resources

Chain of custody for digital assets has become a de minimis exercise. It’s still good practice. It’s still part of the forensic process. But it’s no longer where we should invest our efforts.

Instead, we should be focusing on proof of origin and on developing and refining techniques to confirm where digital evidence comes from, who created it, and whether it is real.

In courtrooms, corporate investigations, and intelligence operations, the challenge is no longer tracking every touchpoint of a file. The challenge is proving its authenticity in a world where digital deception is easier than ever.

This is the future of forensics.

Closing Thoughts: Join the Conversation

This is just one piece of the bigger conversation on the future of evidence. As legal professionals, we need to stay on top of emerging technologies.

Let’s continue the discussion on this LinkedIn post.