In most western democracies I think mass surveillance will counter most efforts by private individuals to get off using deep fakes, I'm much more concerned about police using it to get evidence against people they "know" are guilty. The old scandals of police taking mixing evidence from the scene with dna collected from the suspect, using the latter twice then pointing to it as evidence comes to mind.

I really dont think any country is really ready for what is coming, but I also think its exactly the repressive countries that are in the most trouble, not democracies. Lets say some mid level bureaucrat sees a faked video of Xi telling everyone to spray their airport runways with disinfectant. Does so, cracks down on anyone critiquing it, even if its on reasonable basis such as saying Xi said airports, not airport runways, that they would stop. Lets say the video really gets wide spread, and is something even more stupid, what is Xi going to do? Admit he failed to control the internet, and tell people to think critically about the orders he gives?

Hmm, now I'm going to go tell 4chan to get me the script for the dumbest vaguely plausible thing to have Xi say. A tip btw, you want to create videos of politicians saying something and moving reasonably for a longer period of time, use one of the classic/old face to face transforms, then use that as prior for the deep fake.