Government often exerts itself on the free market (occasionally with great gusto and glee).  Sometimes it is through tax credits — a current program gives a tax credit of up to $6480 for people buying electric vehicles as an inducement for consumers to lower their so-called "carbon footprint".  Sometimes it is through mandates and bans, such as the ban on the insecticide DDT, thought to cause cancer and threaten wildlife (particularly bald eagles).  But it is important to remember that when the government acts to impede the marketplace — even if the effort is genuinely well-intentioned or even necessary to protect public safety — there are always going to be unintended consequences.

In the case of the electric car credit, the (presumably) unintended consequence was to subsidize golf cart purchases, as detailed in this column by John Stossel.  With the DDT ban, while the bald eagle population made a comeback in the United States (commonly attributed at least in part by environmental scientists to the DDT ban), malaria deaths skyrocketed worldwide; in a National Geographic article, Robert Gwadz of the National Institutes of Health claims that the "ban on DDT may have killed 20 million children".

According to this Associated Press story, the Law of Unintended Consequences appears to have struck again.  Across the country, communities have been switching traffic lights from incandescent bulbs to LED.  The LED bulbs use 90% less energy than incandescent ones, and they last longer — Wisconsin's state Transportation Department reports $750,000 in energy savings annually, and the bulbs installed 7 years ago are still in service, compared to 12-18 months for the old-fashioned bulb.  Sounds great, right?

There's one problem — an unintended consequence:  because the LED bulbs are more efficient, they burn cooler.  This is typically not a problem, but it is when there's a snow storm and blown snow obscures the traffic lights.  With incandescent bulbs, the heat from the bulb would melt the snow.  Not so with the cooler-burning LEDs.  The result?  Traffic accidents, at least one of which resulting in a fatality. 

Several countries around the world, including Russia, the European Union, Canada, and the United States have taken things a step further, with their respective governments instituting a phaseout of incandescent light bulbs, culminating in an eventual ban (in the US, the ban takes effect 2012-2014 (depending on various characteristics of the bulb, as per the Clean Energy Act of 2007).  There was, of course, some opposition to banning Thomas Edison's signature invention, notably because of the potential for mercury poisoning.

Is this all just academic?  Well, consider this:  if something as simple as changing a light bulb can result in fatality, just imagine what kinds of unintended consequences could be unleashed by a complete government overhaul of the entire US health care system.  I shudder to think what damage LUI will inflict not just on the US economy, but on the health and welfare of individuals and families.