Here are the questions we get asked the most about driving under the influence (DUI), legal limits, DUI defenses, and finding the right attorney after you've been charged with DUI:

What is the legal limit for blood toxicity?

In general, it is illegal for you to drive while you are "impaired" by drugs or alcohol. It should be clear at the outset that prescription drugs are not excluded from this list. Being impaired means that there must be enough of the alcohol or drug in your system to prevent you from thinking clearly and driving safely while on the road. According to many studies, impairment happens to many people well before they consider themselves drunk or stoned.

As for the numbers if you have a blood alcohol content of .08% or higher, that is considered "per se" Driving Under the Influence (DUI), or Driving While Intoxicated (DWI). For those under the legal drinking age of 21, in almost all states you will be considered to be driving under the influence if you have a blood alcohol content great than .01% or .02%, depending on the state you are in.

What methods do police use for detecting drivers under the influence?

In general, police have three different methods of figuring out whether or not a driver is under the influence:

1. Observing erratic driving -In general, police officers will pull you over if they notice that you are showing any of the signs of driving under the influence. These signs include swerving, speeding, driving too slowly, failing to stop, failing to yield, and any other indications that signal to the officer that you are driving drunk. In general, if you actually have a good reason for driving the way you were driving, the officer may let you go with only a ticket or a warning. However, officers will be looking to see if your eyes are blurred or if they smell alcohol on your breath.

2. Field Sobriety Tests - If, after stopping you, the police officer has a hunch that you may be driving under the influence, he will most likely get you out of the car in order to do some field sobriety tests. These tests can include walking in a straight line, standing on one leg, or a speech test. The officer will also carefully watch your eyes to look for any pupil dilation. If you fail these tests, the officer will likely ask you to take a chemical test.

3. Chemical Blood Alcohol Level Tests - If you fail a field sobriety test, the police officer will likely take you in to perform a more accurate blood alcohol level test. These tests are normally taken by testing a blood, urine or breath sample. The blood test is very direct and measures the amount of alcohol in your system. The urine and breath tests work off of a mathematical formula to derive your blood alcohol level from the sample. If you test above a .08% blood alcohol level, you will be guilty of a DUI unless you can convince the judge that you were not impaired or being unsafe. Also, many attorneys base their drunk driving defense on challenging the mathematical formula used in the tests.

Do I have to take a test if the police direct me to do so?

In general, you are allowed to refuse to take a chemical blood alcohol level test, but if you do, you will invoke an "implied consent" law. This will likely result in a suspension of your driver's license for a period of time, even if you are found not guilty in court. In addition, if your case does go to trial, the prosecutor is free to tell the jury that you refused to take a chemical test, which may look bad for your drunk driving defense.

After I have been stopped for driving under the influence, can I consult with a lawyer before deciding which a chemical test to take?

This depends upon the laws of your state. For example, in Arizona, you may talk to a lawyer before deciding to take a chemical test. However, other states do not allow you to consult with an attorney before a test.

Can the police ask me questions after pulling me over but before reading me my rights?

It all depends on the circumstances and whether or not you are in the "custody" of the police. During a roadside traffic stop, you are not considered to be in police custody, and therefore the police can ask you questions without reading you your Miranda warning. Once you are in police custody, however, they must read you your rights before asking you any questions. If they don't, any answers you give may be inadmissible against you in court. To be in custody, you must feel that you are not free to leave a situation.

I was stopped at a roadblock and asked to wait to answer some questions. Was this legal?

If the police used some sort of neutral policy for picking out which cars to stop, then it was legal. Police are allowed to single out automobiles at roadblocks if they have a good reason to do so, such as a suspicion that you are driving under the influence.

What If I Have More Questions About DUI Traffic Stops?

The best way to learn more about traffic stops, especially as they're used in your state, is to speak with a DUI attorney near you. It's also a good idea to speak with an attorney if you've been charged with a DUI. After all, having an attorney review your case is probably the best way to protect your rights and get the best possible outcome after a DUI arrest.