“This Isn’t Our First Rodeo”: A Legal Perspective on Deepfakes
Starling Lab dispatch from Riana Pfefferkorn’s Stanford talk, arguing that the threat of deepfake evidence is overstated and that the Federal Rules of Evidence already contain the necessary tools to a
Recently, friend of the Lab Riana Pfefferkorn joined the Lab’s flagship course at Stanford, EE292J: Designing for Authenticity, to update the Lab and our students on the current status of federal debates on how best to respond to Deepfakes in the Courtroom.
Riana Pfefferkorn is currently a Policy Fellow at the Stanford Institute for Human-Centered Artificial Intelligence (HAI). Her seminal article Deepfakes in the Courtroom, published in 2020, remains a highly referenced piece (it’s worth a read!) regarding the evidentiary challenges courts may face when addressing deepfakes. It also argues that courts have sufficient tools already to deal with deepfakes—a position that Riana still stands by.
With her permission, here is a summary of her talk as a part of our efforts to keep everyone informed about legal developments and dilemmas about how cheap and accessible gen AI affects evidence.
The Current State of the Deepfake Debate
For the last several years, academics and the United States federal judiciary have engaged in a long debate about whether action is needed to prepare our courts for the looming rise of deepfake evidence (see, e.g., Grossman & Grimm 2025, Delfino 2025.)
Twice-yearly since late 2023, the Federal Courts Advisory Committee on Evidence Rules, the body charged with proposing amendments to the Federal Rules of Evidence, has considered whether amendments need to be made to keep deepfakes out of the courtroom. And, for the last three years, they have continued to decline the adoption of any new rules regarding deepfakes.
To some this may seem puzzling, but as Riana laid out to the students, it actually makes a lot of sense to still avoid raising the bar for admissibility, for two main reasons:
The concern about deepfakes is real, but also nothing new. The challenge of keeping altered, forged, or false evidence from infecting court proceedings has been an issue for every legal system whenever new technologies have arisen, and the rules for authenticating evidence are flexible enough to deal with this one as they have prior threats.
Secondly, the threat of deepfake evidence—that is, evidence which is a partial or complete fabrication but held out as genuine (as opposed to ‘AI-enhanced’ evidence, another category that is being highly debated)—seems to still be unproven. Despite skyrocketing model complexity in generative capability, there has yet to be any large presence of deepfake evidence in federal litigation.
Why Deepfakes are not Particularly New
For as long as we have had courts, we have had litigants trying to pull a fast one. As Riana puts it:
“While seeing has always been believing, we’ve also as a society, known that appearances can be deceiving, and that technological trickery is always possible.”
Indeed, as soon as photography became ubiquitous, so too did the question of manipulations. As early as the 1860s, courts were being forced to interrogate how to respond to fake double-exposed images. So too, in our more recent past, courts have had to come to live with the possibility of photoshopped images.
In Riana’s words: “this isn’t our first rodeo,” and the rules of courts do a pretty good job at enabling us to challenge forgeries. Even within our currently quite open standards for authenticating evidence, there are still ways to use and adjust the application of our rules towards deepfakes without explicitly changing them. For instance, in light of concerns that witnesses could be used to inadvertently authenticate deepfake evidence under F.R.E 901(b)(1) ‘Testimony of a witness with knowledge,’ judges can simply move towards adopting currently more minority interpretations which refuse to accept witness authentication unless said witnesses were actually at the scene (instead of simply, say, identifying the defendant in a video). Litigators and judges can also simply challenge digital items that aren’t up to snuff, attacking their provenance, chain of custody, or digital integrity.
While there are of course nuances here, this leads Riana to conclude generally that we shouldn’t raise the bar for authentication, especially because it’s unclear what it would even be stopping at this time.
Where is the ‘Wave’ of Deepfake Evidence?
Simply put, deepfakes have yet to truly reach the federal courts at any real scale. The Federal Courts Advisory Committee commissioned a survey, sent out in January of this year, which found that 98% of the over 900 federal judges who responded had yet to encounter any deepfake challenges in their court. And of the 15 actual judges who did, only 5 felt that changes to the rules should be considered.
Riana told the class she wasn’t surprised by these results; she has yet to be made aware of a single case where an attorney has knowingly attempted to submit a deepfake into evidence. The reason, she thinks, could be structural: Attorneys have a duty of candor to the court, which critically includes not offering evidence one knows to be false. It’s even Supreme Court precedent: lawyers are prohibited from “taking steps or in any way assisting the client in presenting false evidence,” Nix v. Whiteside, 475 U.S. 157, 166 (1986). As such, presenting a deepfake as evidence is likely too much to risk one’s bar license or even just one’s credibility in front of the court. And while there are a few cases where pro se litigants (those who are unrepresented) have tried to submit deepfakes as evidence, judges have successfully been able to reject such evidence on grounds familiar to the court.
Thus, despite warnings of a coming tide of deepfakes in the court, very few have yet to materialize. But one prediction has in fact become true: Citron’s and Chesney’s “Liar’s Dividend” or ‘the deepfake defense.’ This occurs when, in light of damning authentic evidence, parties attempt to claim, with no supporting materials, that such evidence must be rejected on the grounds that it could possibly be a deepfake. Luckily, courts haven’t bought this either, finding such arguments dubious and ridiculous.
What Concerns Do Remain? C2PA & Worsening Disparities
So, courts seem to be able to address deepfakes under the current rules just fine, and deepfakes don’t seem to be that common… So what is still at stake?
For Riana, the new technologies we may rely upon for additional certainty of authenticity, even under the same rules—provenance technology like C2PA—risks creating access barriers:
“One potential ramification of a world where some people have access to (...) the $9,000 cameras that have C2PA in it, and [where others] just have regular, run-of-the-mill smartphones, is that it may exacerbate existing disparities in who gets believed when they testify or produce evidence, and who does not. (…) Similarly, I think that if you look at who already comes from a disadvantaged socioeconomic background and therefore is not going to have a $9,000 camera (…) they are also going to be less likely to be believed when they do have authentic evidence.”
This is particularly an issue if we consider how, once jurors become aware of the existence of C2PA or other systems of content provenance, attorneys may be able to prime juries to be extra skeptical of images that lack it (known as the “Reverse CSI Effect”)—enabling their pre-existing biases about people to take root over the evidence being shown or its credibility.
Conclusion
Deepfakes in the courtroom remain a theoretical threat as much today as when Riana first wrote her piece. But the debate today seems to understand that the chances of completely fabricated generated evidence overwhelming the courts and making current rules and practices unusable is unlikely. Nonetheless, as provenance technologies become more mainstream and as prosecutors and defense attorneys alike explore more ‘edge’ cases of AI (such as the aforementioned “AI-Enhanced” debacle), it remains important to keep on eye on what arguments are being made and which are successful. The Law is, as always a constant battle, and just if the rules stay the same doesn’t mean that the results are guaranteed to further access to justice.
Thank you so much to Riana Pfefferkorn for joining us at the Lab!