This is like someone who removes a brake pedal from a tractor, uses a stick to hold down the throttle, and lets it loose on his field. When it leaves the field and runs someone over, that is criminal negligence.
If the prosecution is able to prove beyond a reasonable doubt that the person gave a prompt that was intended to commit a crime, then of course we can prosecute them for that. The AI is just a tool to commit fraud at that point, and is no different than a person who uses photoshop to alter a check to commit fraud.
That doesn’t mean you can get away with anything as long as you don’t intend to commit a crime; there are many other crimes that don’t require intention at all, like involuntary manslaughter or gross negligence.
My point is that if you want to charge someone with a crime that requires intention, you have to prove that intention.
Of course, it'd be better to not regulate, keep LLMs users reponsible and publicize this reponsibility in order to mitigate damage. But if this is not enough then we will have to move the needle somehow. Similarly to guns, drugs and so on.