Is filing our taxes dangerous to our health? Some researchers found a statistically significant uptick in road fatalities on tax day. My gut tells me this is one of those moments when random chance gives us this result—the study says there’s a five percent chance this was a fluke. But this story has been mentioned in many news outlets because it fits perfectly into the narrative that our tax code is unnecessarily complex and full of stress-inducing uncertainties.

Thus the latest post in my tax reform series covers the complexity of the tax code’s and how is creates uncertainty.

How big is tax code? Try 3.8 million words, according to the IRS, with 4,430 changes made between 2001 and 2010. Yet these changes haven’t made the tax code better. Businessweek reports on how easy it is to make a mistake [emphasis mine]:

In 2006 the IRS studied 46,000 audits of taxpayers. Among those returns that were flagged for misreporting income, IRS auditors reported 67 percent of the problems were unintentional errors; 27 percent were computational errors either caused by the IRS or the filer; and 3 percent of mistakes were intentional.

How much does the tax code cost? In 2010, the IRS estimated “that the costs of complying with the individual and corporate income tax requirements for 2008 amounted to $163 billion – or a staggering 11 percent of aggregate income tax receipts.”

The tax code’s costly complexity plus Washington’s inability to act on expired tax provisions equals needless additional economic uncertainty facing businesses. The biggest uncertainty is the future of the 2001 and 2003 tax cuts. If Washington doesn’t act by the end of 2012, they will expire, and America will endure one of the biggest tax hikes in its history.

Add this impending deadline to the R&D tax credit and more than 100 other provisions that have either expired or will expire and one shouldn’t be shocked that businesses are holding back on future investments. No new investments mean no new jobs created. Our sluggish economy recovery will vanish.

We need comprehensive tax reform that is a set of simple, predictable rules that individuals and businesses can easily comprehend and comply with. Reform also must ease uncertainty and create a better environment for businesses to expand, create jobs, and remain globally competitive. We’ll end up with a stronger economy and maybe even safer streets.