Drunken Driving (DWI) Law Challenged

Virginia General District Court Judge Ian M. O’Flaherty has found that the state’s DWI laws make some unconstitutional assumptions.
Prosecutors argue that Virginia’s DWI law creates “rebuttable presumptions,” which means that the defendant has the chance to try to prove them wrong. Judge O’Flaherty says that the DWI law improperly shifts the burden of proof from the government to the citizen.

Citing a 1985 U.S. Supreme Court ruling the judge says that requiring defendants to do or say anything in their defense violates the Fifth Amendment of the Constitution. In criminal cases, such as DWI, prosecutors must prove defendants guilty beyond a reasonable doubt. On the other hand, defendants are not required to do or say anything to defend themselves because the burden of proof falls entirely upon prosecutors. Judge O’Flaherty says the Fifth Amendment “is an absolute protection against requiring the defendant to say or do anything in the course of a trial….”

In Western democracies, defendants are presumed innocent until proven otherwise. It’s only in dictatorships and police states that defendants are presumed guilty and must prove their innocence.

The DWI law presumes that a driver with a blood alcohol concentration (BAC) of .08 as estimated by a breath alcohol machine is intoxicated and guilty. In reality, many people are not intoxicated at that level. Research has demonstrated that about one-fourth of alcoholics at the higher .10 level show no clinical signs of intoxication because they have developed a tolerance for alcohol.

Judge O’Flaherty also questions the presumption that a BAC reading taken an hour and one-half or longer after an arrest, when most such readings are taken, is the same as it was at the time of arrest. The Kentucky Supreme Court has recently overturned a case that was based on that very assumption.

Criminal law professor Ronald J. Bacigal of the University of Richmond says “I think he’s exactly right. There are U.S. Supreme Court cases saying you can’t relieve the government of proof beyond a reasonable doubt, which is what a presumption does.”
The head of the National Association of Criminal Defense Lawyers’ DUI committee, Steve Oberman, says that similar arguments about the law’s presumptions have been successful in courts across the country. For example, state supreme courts in Massachusetts and Colorado have ruled exactly as O’Flaherty has done on the issue of presumptions in drunken driving cases.

The Washington Post reports that “The judge is well regarded by lawyers who practice before him and has received high marks in Fairfax Bar Association evaluations.”

It’s very important to prevent drunken driving and save lives. But it’s also essential that we don’t violate basic constitutional rights of citizens in trying to do so.

The matter is expected to be argued before the Virginia Supreme Court.


  • Jackman, Tom. Maverick N.Va. judge tosses out DWI cases that presume guilt. Washington Post, October 27, 2005, A01;
  • Jackman, Tom. Va. Drunken driving law challenged in Fairfax court. Washington Post, October 28, 2005, B08.

Filed Under: Drinking and Driving