The risk of someone dying due to distraction and a failure to avoid an out of control car is dramatically less than the risk of someone dying due to getting bored and jaywalking into traffic.
Not sure how many countries have jaywalking type laws, but in every country I have lived in or or been to, bar the US and (after reading the below link) Singapore, it's just called 'crossing the road http://en.m.wikipedia.org/wiki/Jaywalking
The legal situation isn't particularly relevant so much as whether or not people will decide to cross the street before the light tells them to, and whether that has a higher probability of accident.