When your photo is taken for your driving license , why they do tell you smile?

May be it is like this: They want you to smile atleast in the photo! And by the way, Its not that much strict in my place, when we are caught, the policeman himself smiles, which means he is expecting something.... When he smiles and scratches his head, we must understand that and fulfill his needs.

LOL. that is exactly what my friend told the lady that took her picture. She said smile my friend said Why? I am not going to be smiling when the cop pulls me over.. LOL.. She started laughing! It was funny- I think she made her smile anyway. I personally do not like to smile for my pictures. :(

If it happens to me, I would smile at first. We have a regulation here that the police should smile and salute when excute the routiees. Why don't you smile as well? Keep smile all the time lol