Bystander cellphone footage is often used as evidence in courts, at least in the USA.

This comment seems to imply that all court admissible video evidence comes from trusted chains of custody and thereby trusted sources, which isn't necessarily the case.

>This comment seems to imply that all court admissible video evidence comes from trusted chains of custody and thereby trusted sources, which isn't necessarily the case.

What's stopping a defense attorney informing a jury about DeepFakes and having that fact factor into their "beyond a reasonable doubt" criterium for criminal cases?

DeepFakes have more potential in PsyOps than legal cases.

Just informing them of that possibility will render such evidence basically useless. Once video can be faked where it can no longer be detected, video just doesn't carry any more information than, say, "we got this anonymous letter saying the defendant is guilty".

So, yes, that information should be given to the jury (as soon as it becomes accurate), and it will lower the potential for false positives (convictions), but with an equal and opposite increase in false negatives.

> Just informing them of that possibility will render such evidence basically useless.

Is a verbal statement from an impartial witness useless? What if they say recognise the defendant as the criminal they witnessed? Obviously it's not as ideal as unfakable video evidence, but it is useful and has been the basis of legal systems for the millennia before computers and photography arrived.

Fakable video evidence is somewhere between these: you still have to account for the possibility that the person isn't honest, but don't have to worry about the fallibility of human memory.

Assuming, of course, that currently video is an equally occurring factor in both values and invalid convictions

No, no, that's not what he's saying. He's saying that in court, proving the provenance of a piece of physical evidence is more important than the technical factors of the thing itself. But what everyone is focused on with deep fake videos, is how technically good they are.

My daughter's birth certificate could be reproduced 100% indistinguishably by a Fedex Office print shop. But it is backed up by a chain of people who, if necessary, will testify that it is authentic.

People think that testimony requires physical evidence to back it up (look at the reaction to Dr. Ford's accusations). But the legal reality is the opposite... physical evidence is only useful at trial to the extent that credible testimony can establish its authenticity and relevance.

So a deep fake video that looks exactly like a real video will only be useful at trial if it can be established as credible, by the testimony of credible witnesses.

All that said... there is more to life than the justice system. Forgeries have always taken in the gullible, so deep fakes will undoubtedly have a social impact, especially in the early days before the public is generally aware of the capabilities. This is undoubtedly one reason the press is starting to cover this technology so aggressively.

I was on a jury in a murder case that was decided by evidence from a surveillance camera (actually two of them, from different angles).

If it's possible to fake HD video, it's also possible to fake grainy surveillance camera footage. If you prove the defendant was in a particular place, and you produce video purportedly from a surveillance camera in that place, a jury would believe it.

Forgeries do have significant impacts. Everything from beef being photoshopped into meals leading to violence (e.g. in Hindu regions), to significantly impacting the burden of proof required for prosecution of war crimes.

And that's not even considering what you can do without an actual forgery, just by messing with context e.g. https://www.buzzfeednews.com/article/meghara/we-had-to-stop-... https://www.nytimes.com/2018/04/21/world/asia/facebook-sri-l...

If "deep fakes" become easier to create than mis-contextified video, they can and will be used to spark conflict in areas with simmering tensions.

I say this as someone actively involved in avoiding the worst case scenarios; I wrote a piece here with more detail: https://www.washingtonpost.com/news/theworldpost/wp/2018/02/... (though HN is not the target audience).

[first paragraph repeated from another comment below]

I’m not sure why the below comment is dead - it’s a valid point. My worry regarding deepfake videos is their political and social consequences

Exactly -- many assertions fall very far from being prosecutable but can be enormously disruptive socially.

See the recent SCOTUS nominations for an example.

... and that's in a modern well-educated society.

In countries that are riven by sectarian and tribal rivalries, a convincing video can result in the deaths of millions.

We've already seen that internet conservatives will prey on the elderly and other susceptible types on Facebook with fake news. And it works. Even if it gets retracted or disproved later (and not everyone sees the disproving), the false image has been imprinted. I expect this to be used in this way shamelessly.

Stop the fear mongering.

Things will be fine, we'll have a few minor hiccups to resolve, but that will be it.

Some people really underestimate human ingenuity, do you really think that we won't be able to solve this issue in a manner of days if need be? Come on..

We're a few decades away from AI and immortality, and some people are worrying about fucking politics?

Think long term, and chill out.

There is a lot more than just law enforcement to worry about. Deepfake videos can and will be a tool for political propaganda.

Exactly. A popular fake video of a person doing something bad may not put them in prison, but can prevent them from being elected.

Also, a fake video of them tearing up a holy book can get them killed.

Personally I think the reaction to deepfakes has all of the hallmarks of a moral panic - a widespread reaction and banning of it on all sorts of forums and repositories even though they previously had no issues with 'fake' celebrity images or videoes perhaps out of stereotypical corporate blame aversion bubbling up. The language used was a deliberate conflation with invasion of privacy with 'nonconsensual pornography' - and that was in official policies.

A lot of CCTV footage from modern security systems are capable of high-definition and can zoom in on many portions of a frame.

But yeah, as others have said...I'm more worried about the political and social consequences of doctored videos. We already have a culture that is triggered at the slightest sign of perceived injustice. What if that injustice is a fabricated lie, architected by troll farms?