When I sit in the passenger seat–as an experienced driver myself–I’m usually as attentive to traffic and road conditions as the driver. Not having my own set of mirrors is a bit of a handicap, but to offset this, I can perform a 5 second shoulder check and not lose my lane. When the passenger is paying the same attention as the driver, the conversation naturally shapes itself around cognitive load. The driver doesn’t need to signal a pause. Often it’s the passenger who senses the upcoming lane change, and initiates the pause. The passenger can afford to devote considerable mental resources to discourse management. Discourse management is major subfield within linguistics, and not appreciated nearly as much as it should be, to the enrichment of marriage counsellors everywhere.

What do studies have to say about the limit on how much can be communicated without any detectable loss in driver aptitude? I’d be shocked if anyone has bothered to find out. Who funds that? One might even discover that an astute passenger can, in the best case, function as an anti-distraction. No insurance company wishes to learn this.

The cognitive burden boils over when the conversational partner falls short of full situational awareness. This can be a child, or a distracted, restless, insistent adult. Worse still if the conversation partner isn’t even in the car: zero shared situational awareness. Even so, if you’re talking to sibling and you’re not at cats and dogs over anything, the required silences during the driving activity will likely manage themselves through long familiarity.

A hundred times worse, you’re talking to your boss (managing up), a difficult subordinate (managing down), a client you need to impress (on the make), making social commitments you might later regret (double booking), or discussing any social nuance where clout matters (status conscious). Managing our place in the social hierarchy is a full time job for our giant brains. Lucky if we humans don’t fall our tree branch trying to do two things at once. Half the people who come into my coffee shop can’t manage to close the door behind them on a cold October day if they’re yammering with a chum on the way in. Do you want these people out there driving cars? With a phone?

Definitely many accidents are caused by drivers who are in the wrong conversation at the wrong time. If we’re going to police this at all, the rule needs to be shallow. It’s not the cop’s job to determine if your brain was preening, or not, in a particular exchange of words.

I think it has to be up to the driver to judge the risk, because a lot of valuable economic activity happens on the road in the transportation and sales industries at very low accident risk. There needs to be painful consequence on judging this risk badly: such as having twice as many points slapped on your license if you get into an accident (regardless of fault) while yammering on the phone. We could also require cars to signal “phone active” with a rooftop warning light, to make it easier for the cops to pull someone over who isn’t driving as well as they think they are. Intrusive? Any idea what’s on your hard disk already watching your every move? I thought not. Trust me, Google knows.

If it’s the cop’s discretion that bugs you, maybe it’s time to give your jaw a rest already. Do you have nothing at all in your mind to contemplate in solitude? That’s a sad state of affairs. Too many people severed from their mobile phone yowl like someone’s overdependent pet dog leashed outside the coffee shop by the same people who can’t manage to close the door on the way out to their asphalt-coloured tinted-window antenna-laden SUV.

I think Ontario’s law is well intentioned, but suffers from one serious problem: It is simply NOT possible to legislate stupidity from the human race. Accountability can be legislated into the law, but stupidity cannot be legislated out of the law.

Think about it.

You’re over exaggerating the extent of the law. I suggest you read a summary of it, or read the law itself.

http://www.e-laws.gov.on.ca/html/source/regs/english/2009/elaws_src_regs_r09366_e.htm

Read the law before you start making stuff up.