Why do Virginia DUI / DWI laws deal with the amount of alcohol in my breath anyway? Isn't the amount of alcohol in my blood what is important?

A: Great question!  It's common knowledge that alcohol and drugs will impair your ability to safely drive a motor vehicle, and drunk driving laws are intended to address that risk.  And yes, lawmakers only care the amount of alcohol in your blood (not on your breath) because impairment is caused when the alcohol reaches the brain, and the way alcohol reaches the brain is in the blood.

It's really not possible (and certainly not practical) to directly measure the amount of alcohol in the brain, so we have to find another way to try and figure out how much alcohol may be in the brain.  The best way to do this is to measure the amount of alcohol in the blood since it is blood that carries alcohol to the brain.  The traditional drawing of blood and sending it to the lab for testing is possible, but it is both time-consuming and costly, and lawmakers would obviously prefer a quicker less expensive method of determining blood alcohol content.

Enter breath alcohol testing.

Breath alcohol testing is based on the premise that there is a known, constant ratio between the amount of alcohol in your blood and the amount of alcohol in your breath - so if we can accurately measure the amount of alcohol in a person's breath we can calculate the amount of alcohol in that person's blood.  Interestingly, breath alcohol testing is not only easy to administer and incredibly quick, but also dirt cheap in comparison to blood testing.

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The lawyers of The Wilson Law Firm have traveled Virginia’s several interstates helping clients just like you - appearing in courts all across the Commonwealth of Virgnia - from Virginia Beach and Norfolk in the southeast, to Wise County in the southwest, all the way up I-81 to Frederick County / Winchester in the northwest, and all the way across Warren County, Fauquier County, Prince William County, and Fairfax County on the way to Arlington County and the City of Alexandria in the northeast. The Wilson Law Firm regularly serves Prince William County, the cities of Manassas and Manassas Park, the towns of Haymarket and Quantico, Fauquier County / Warrenton, Stafford County, Spotsylvania County / Fredericksburg, Loudoun County / Leesburg, Fairfax City, Fairfax County, Arlington County, the City of Alexandria, Culpeper County, Warren County / Front Royal, Clark County / Berryville and Shenandoah County.