Squigly Squigly's Brain Teasers

Question:

A man and his wife were driving in a car, when the wife's behaviour caused him to stop the car and rush to the nearest house. When he returned to the car, he found his poor wife at death's door and there was a stranger in the car with her. When the police arrived, they did not arrest or even question the stranger. How come?

Answer:

The woman had delivered a baby.

Try another Brain Teaser:

An electric train is going 40 mph north, the wind is blowing 60 mph south. Which way is the train's smoke blowing?