DWI Information
In October, 2000, Congress passed a law requiring all states to adopt a limits of 0.08% by 2004 or lose some of their Federal highway funds, so it is likely that many more states will adopt that lower limit.

Apart from the general 0.08% to 0.10% limits, some states have "zero tolerance" limits for young drivers.

Most European countries have limits that are far below 0.08%. You may be considered "legally drunk" even though you do not "feel" or look as though you are under any "influence" from the alcohol .

DWI Answers
Breath tests are the least accurate in determining the amount of alcohol you have in your system. This is because the breath machine assumes that the breath is from the lungs when it may be the alcohol residue still lingering from the mouth, esophagus, or the digestive system. If you belch, burp, hiccup, or vomit shortly before testing, or take a "breath freshener" (e.g., Binaca, Listerine), or cough syrups, you can bring vapor from alcoholic beverages still in the stomach up into the mouth and throat, registering an inaccurately high reading that would be used against you. Dental bridges and dental caps can also trap alcohol.

Analysis of a blood sample is potentially the most accurate, since it shows the presence of both alcohol and drugs. The least accurate and least reliable, by far, however, is urinalysis.

Thus, if you are confident that you are sober, a blood sample is the wise choice; urine, being least accurate and most easily impeached, is the best option if you believe your blood-alcohol concentration is above the legal limit.