from my point of view, asking for statistics on ppl getting into accident due to watching lcd screens is like asking to do a statistics on ppl getting into accident due to bald tires. We know that it is dangerous to drive around on with bald tires, as it is the characteristic of the tire to work properly only if it have enough thread. And do we see any news report on accident being caused by bald tires? though we sometime have the idea that most accident which happens in rainy days are caused by this, but we just don't have the statistics to prove on this, as we are just too obsessed with the phrase that "speed kills".
Same goes to having monitor which is in view of the driver. We all know that it is human characteristic and psychology to even get excited over something interesting, even for a short period of time. For example; We can't deny that we sometime see men get distracted when a pretty woman pass by, and somehow they land themselves in trouble after that (we can see this classic example in movies, though it is fictional but it is based on real life scenario) though it was only for a short period of time. Even for a split second that our eyes are off the road, something big can happen, and we all can't deny that. As all accidents happens in a split second, and it is hard to prove that such accidents are caused by monitor screens, but we all know that it is plausible. And as for GPS monitor, I believe that most GPS comes with voice command. And you don't even have to look away from the road ahead. Even if you really have to look at the GPS monitor, it will be in a cautious manner, as people who are lost, will certainly be VERY alert as they wouldn't want to miss even a junction.
And I would support if these items (monitors which are in the view of the driver) be banned from selling. But this is not as simple as 1+1=2. When there's demand, there will always be a supply. That's the world we live in. As long as there are demand for such monitors in the market, accessories shop will still be selling it, even though that it is illegal to do so, just like rokok kretek. So, by really imposing this law, I think it will help reduce this demand, and somehow would eventually put a stop to it. Though it may take such a long time to see the fruit of doing so, I believe it will be well worth it. Just like wine, you don't get the best wine right after you squashed the grapes, but it will take a lot of time to ferment it, to produce good wines.
p/s; would you put live on wire if you know that there is a plausibility for it happen? "Prevention is better than cure"