Unintended consequences

The freakonomics blog http://freakonomics.blogs.nytimes.com/ at the NY Times (registration required) had a long article on the law of unintended consequences. There were some references to Andy Gelman's comments http://www.stat.columbia.edu/~gelman/blog/

Here's my example of another law with a positive unintended consequence. Car-ifornia has instituted laws required young (under 18 years old) aspiring drivers to practice driving at least 50 hours with an adult 25 years of age or older. For most teens, this means they need to negotiate 50 hours of driving with their parents.

The unintended consequence? The 16 year old (in my case) will be spending a forced 50 hours with their parents. To negotiate this, they will need to maintain good relationships with their parents. This law may have the accidental affect of improving family relationships more than almost any other possible law I can think of!