Something I've never understood about articles like this is why they would claim that driverless cars are illegal.
They're not. Not in my state, and not in any state that I'm aware of.
Under the standard legal premise of "that which is not prohibited is permitted" that operates in the vast majority of the world, there are no laws which ban driverless cars. Automotive laws specify quite a few things, but most of those apply to:
1. The car. A car has quite a few things that it's required to have. Things like headlights, turn signals, windshields, tail lights, air bags, seat belts, etc. A driverless car could have all these things, and likely would have them. If they're all there as required, the car is legal.
There are also things a car is not allowed to do. For example, it's not allowed to be in certain places, and it's not allowed to be in other places for more than a certain amount of time. It's not allowed to go through a red light when there's a scamera at that light. It's not allowed to go above a certain speed when there's a scamera. Tickets for these things aren't given to the driver, they're given to the car or sent by mail to the car's owner. An automated car could certainly handle those rules, probably better than most humans. Because until now cars weren't capable of traveling without human supervision, there was no need to write laws that would apply to the car doing that. And if there's no law prohibiting it, it's legal.
2. The driver. There are lots of laws that apply to a driver. They specify what a driver can and can't do, what he must wear, what he must possess, and how he should behave in various situations on the road. These laws apply to a person. They are written to be completely inapplicable to a car, as there was no need to make them apply to the car. And if they don't apply to the car, they're simply irrelevant to a driverless car.
So I would say that no new enabling laws actually need to be passed at all. The existing legal structure is sufficient in most places for driverless cars to be on the streets today.