California is considering a ban on cell phone use while driving. Hands-free phones will still be permitted. The informal and published debate about this is interesting because of a seemingly desperate desire not to believe the well-established facts, which are (1) Using a cell phone while driving is about as impairing as being just at the legal alcohol limit; (2) a handsfree phone is just as bad as a handheld one. The law should rule out any phone use while driving, and anyone doing it, legal or not, should be an object of social scorn, right up there with drunk drivers.
I find these results perfectly match my intuitive sense of how much worse I drive using a cell phone, whether or not I’m dialing it or have a hand occupied holding it up, and I have completely forsworn this behavior. What’s interesting is that the handsfree option doesn’t help; after all, you can safely converse with someone in your car while driving, and you can listen to the radio. I believe the problem is that a phone conversation demands your attention and response, unlike the radio, and that the person on the other end, unlike your passenger, can’t see what you see through the windshield nor see your visual behavioral cues. The passenger will stop talking instinctively when something important is happening on the road, or when you tense up, but the other party on the phone can’t do this.
I’d like to see someone with the right lab setup test this conjecture; the critical experiment would be to have a driver talking on a handsfree phone with a partner in another room who’s watching the same simulator display as the driver, and maybe watching video of the driver as well. I bet driving would be very little impaired.