Here in Phoenix, robo-taxis are a hot ride. Open up the app, choose a destination, and just a few moments later. All right, the car is here.

I'm going to use the app to unlock it. And away we go.

Hello, Valerie.

So we just hopped in the waymo.

There is no driver behind the wheel, and we're going to go pick up the mayor of Phoenix. The robo taxi, owned by Google parent company Alphabet, It takes us for a smooth while cautious ride. The steering wheel turning as if an invisible hand is guiding it. And when we get to a stop sign... Complete stop. We reach our destination with no issues. We've arrived. Good morning.

Good morning.

How are you? Excellent. Phoenix mayor, Kate Gallego, is a big fan.

Waymo drivers don't have the bad days that human drivers do.

Do you think this is safer than an actual human being behind the wheel?

The technology can see so many more things and process it so much more quickly. I think in the long term, it will be safer.

Why is this working so well here in Phoenix?

I think we've been very open to the technology, and there have been There are political challenges in other communities that we have not had. We have an open grid system of streets, and so I think that is probably a little bit easier to navigate.

But incidents like this low speed crash into a telephone poll in May, leading to a software recall of its Phoenix fleet, more than 600 cars. The robo-taxis caught on camera making other mistakes, turning into oncoming traffic in Tempe, swerving in and out of its lane, driving into a construction zone, and ignoring an officer's instructions to pull to the side of the road. Sir, there's no one there. Waymo declining to comment on specific incidents, but adding that they continue to refine the technology. Waymo is the subject of an investigation by the National Highway Traffic Safety Administration for various collisions saying several incidents involved collisions with clearly visible objects that a competent driver would be expected to avoid. Waymo saying in part, NHTSA plays a very important role in road safety, and we will continue to work with them as part of our mission to become the world's most trusted driver. In other cities, driverless taxis are also making headlines. Weymo, going the wrong way. A cruise vehicle owned by General Motors and a competitor of Weymos running over and dragging a woman who had just had been struck by a hit and run driver last year in San Francisco.

In a statement, Cruz said, its car breaked aggressively to minimize the impact with the woman after the other car launched the pedestrian directly in front of the cruise vehicle. Regulators temporarily suspending the company's permits. Waymo criticized for causing traffic jams and stopping in the middle of the street. Hi, how are you? Crossing guards telling NBC Bay Area they've nearly been hit in the crosswalk. It did not recognize me in the inner section. But back in Phoenix, Waymo says it's growing, dominating 315 square miles around the city, the largest Metro area it serves in the country, and it's the only robot taxi that picks up and drops off at a major airport. Andrew Maynard is a professor at Arizona State University School for the Future of Innovation in Society.

Waymo, as other companies that are developing similar technologies, are still learning. So it's not 100 % safe. If we have a technology that occasionally runs into poles, Maybe that's the price to pay for developing a technology which will ultimately, hopefully, be safer than humans.

Removing the human element is why a community group called Phoenix Babes Who Walk partnered with the company, calling it a safer option for women and members of marginalized groups traveling alone who might encounter a bad experience with a ride share driver.

We've had folks who are gay or lesbian, and they're afraid to get into their car and hold their spouse's hand because of what might happen with their driver, a comments that may come up unsolicited.

While the tech continues to improve, some believe it could become the norm down the road.

To me, the most exciting scenario is that we use self-driving cars as a stepping stone to a future where we have completely a lethal transportation.

Okay, Valarie Castro joins us now, live, Valarie. Fascinating report. I want to start with something we saw there. The police officer, he was trying to move the Waymo car out of the way. How does that work?

So So just like any human driver behind the wheel gets better with experience, so does this technology. And Waymo says they actually train with law enforcement and other first responders for emergency situations. And they actually sent us some video that shows the car interpreting a situation using AI technology. And here, the traffic lights are out at this intersection. And so the Waymo sees a police officer in the middle of the road and sees the officer eventually waving it through the intersection. So it is interpreting the officer flagging it through. And It also can see sirens, say there's an ambulance behind the car. It will also pull over when it sees that.

Talk to me about the regulations here. How was Phoenix able to figure this out?

Phoenix has been a big champion of autonomous vehicle technology, and the former governor, Doug Ducey, actually signed several executive orders that reduced a lot of the regulations and allowed for these vehicles to be tested on public roads. Of course, now it's expanded to the public actually using these vehicles.

I can remember when Uber started expanding, and a lot of cities fought Uber, now Uber is all over the world. Is that what's happening with Waymo? Are they expanding to other cities?

They are. Just today, as we mentioned, San Francisco is now an open market. All users in San Francisco can use it. Previously, they had a waiting list. Waymo also operates in limited capacity in Los Angeles, in Austin, Texas. So they're continuing to grow.

Okay, I definitely want to try it, but I got to tell you, I was watching your video. It made me a little nervous. You did it, I think, four times you told me. Talk to me. I mean, were you comfortable with it by the end?

What was the first experience like? Look, the first one is definitely unnerving. I mean, you look in the front seat and there's no one behind the wheel. It's turning by itself. It's taking left-hand turns. But after a while, you're pretty comfortable with it because look, it's not going to go past the speed limit. The driver is not going to have road rage. You're not going to have to worry about a drunk driver behind the wheel, anything like that. So the car actually goes slow, and it's boring after a while, to be honest.

Did it get to a point where you lost yourself? You were able to zone out or check your phone and not be constantly focused on the road?

Yeah, it's nice. And we watched it, stopped at the stop sign. It was cautious. Again, the ride was boring after a while because it follows all the traffic laws.

Again, Valarie, an amazing report. Really insightful. We appreciate you and your team, what you guys did there.

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