If you don't actually have a real policeman in your village, you can make a model of a policeman, and stand him by the roadside. People will slow down. Trouble is, the police don't actually wear white spats any more, and the average cop is a bit taller these days.
If the population of your ville is thinning out, why not put up some decoys to attract some real people, as is done with ducks? This is clearly an individual initiative, but if it were undertaken at the municipal level, it might actually work.