When you enact economic policy legislation, setting the effective date is very important. Usually, you want to avoid a rush to market by the first to hear while you're in the middle of legislating, so you choose the date of the first public announcement. Often you set the date of enactment, when the president signs the bill into law because only then is it certain the law will be put in place. Retroactive effective dates are a no-no, because they trap people without warning, particularly tax increases on activities that have already occurred. Sometimes you set a future effective date to allow those affected time to comply. That was the thinking behind the Expedited CARD Reform for Consumers Act of 2009 that President Obama signed into law on May 22, 2009 with effective dates in February and August of next year. However, banks are using the interim to jack up credit card interest rates.
