Martin Krenn, Aisling O’Beirn
5 min
This study explores how physical objects and technical systems function as witnesses to history. By examining the "material witness," the authors shift the focus from human testimony to the ways in which nonhuman matter—such as damaged cathode ray tubes or environmental changes—registers and archives external events. This approach treats these objects as "double agents" that harbor direct evidence of occurrences while simultaneously exposing the institutional and epistemic frameworks that allow such evidence to be recognized and utilized in political or legal contexts.
The authors use the example of "screen burn" on a derelict CCTV monitor from the Maze/Long Kesh prison to illustrate this concept. The permanent, ghostly image etched into the phosphor screen serves as a material trace of years of surveillance. Although the screen lacks kinetic information—it cannot show the movement of people—it remains a "material witness" to the coercive power and architectural control of the prison. This demonstrates that even when a technology is defunct, its material state retains a record of the political violence it was designed to observe.
Moving beyond traditional criminal justice, the paper redefines "forensics" as a mode of assembly rather than a simple deductive science. By drawing on the work of Forensic Architecture, the authors argue that forensics should be an imaginative process that brings together media, science, and law to create new political configurations. This method does not seek to uncover a single, objective truth but rather aims to open up the expressive potential of things, allowing them to participate in the construction of public truth and historical memory.
In an era of "post-truth" politics, the ability to verify events is often contested. By expanding the definition of witnessing to include nonhuman entities, this research provides a new lens for understanding how we can reconstruct histories of violence and state power. It bridges the gap between the material world and the juridical, suggesting that our understanding of evidence must evolve to account for the ways in which matter itself is "informed" by the events it experiences.
Sam: Though I'd imagine there are real limits to what this approach can tell you.
Alex: Significant ones. The screen can confirm that a particular space existed and looked a certain way. But it can't show you the dynamic movement of people through that space. It's a witness to the environment, not necessarily to every specific act. So it contributes a piece of the picture, not the whole thing.
Sam: Which means the real skill is knowing what questions to ask of these objects—and understanding what they can and can't answer.
Alex: Well put. And the paper pushes that further by asking a broader question: who and what counts as a witness? It's about expanding our idea of testimony to include the material world, even when that world has been damaged, altered, or deliberately silenced.
Sam: That brings up something I've heard about with magnetic tapes—the idea that old recordings leave behind faint traces even after something new is recorded over them.
Alex: Yes. To understand that, you first need to picture what a magnetic tape actually is. It's essentially a long strip coated in millions of tiny magnetic particles—think of them like microscopic compass needles. When you record something, those needles get rearranged into a specific pattern. That pattern is your recording. When you record over it, those particles shift again—but not completely. Residual traces of the original pattern can persist underneath the new one. The technical name for this is "hysteresis."
Sam: It's a bit like writing in pencil, erasing it, and then writing something new—but if you hold the paper at the right angle, you can still see the indentation of what was there before.
Alex: That's a clear way to put it. And the implication is significant. Erasure, in this context, is just adding new information on top of old information. The old data isn't truly gone—it's buried. With the right tools, it can potentially be recovered.
Sam: So even media that's been deliberately overwritten could still carry evidence of what came before. That has real implications for cases where someone has tried to destroy a record.
Alex: It does. And the paper frames this not just as a technical observation, but as a philosophical one. It challenges the assumption that destroying or overwriting evidence is the same as erasing it. The material world, it suggests, is more persistent than we tend to assume.
Sam: So the argument isn't just "we can recover deleted files." It's something deeper—that matter itself resists being silenced.
Alex: That's a fair summary. The research is asking us to reconsider what counts as a record, what counts as a witness, and how we read the physical traces that events leave behind. It's a framework for listening to objects that can't speak for themselves.
Sam: It makes you think differently about the things around you—that the physical world is quietly accumulating a history we rarely think to read.
Alex: And that reading it carefully, with the right methods, might tell us things that no human witness ever could. Thanks for listening to ResearchPod.