[jhrobert]

I've read studies that say that talking to a passenger is distracting, hence dangerous.

Well... I haven't read such studies actually, yet. But I feel like it's safer to stay at home, and shut up, and let the villains rule the world. Kidding.

I believe that trading liberty for safety is the true danger. That's because there is no point in expecting a sense of responsibility in the mind of people without freedom. Freedom and responsibility go together, remove the former, you remove the latter.

[bryanlarsen]

Actually, studies have shown the opposite, talking to a passenger is less dangerous than driving alone. A passenger is part of your shared environment and reacts to road conditions. They also keeps you awake and alert.

"Your freedom to swing your fist ends when it comes into contact with my nose." I think this trite phrase applies here. You're not just risking yourself, the risk to others is very high and demonstrable.