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Should I Take a Police Breathalyzer, Urine, or Blood Test?

It is not uncommon for a person to have an alcoholic drink with dinner and then drive home safely. However, the more alcohol you consume, the more dangerous it can be to drive home. If police pull you over on suspicion of driving under the influence of alcohol (DUI), the officer may ask you to take a portable breath test. If this breath test shows that you have a blood alcohol content higher than the legal limit (.08%) you will likely be arrested. Once at the police station or jail, you will have to submit to a Breathalyzer, blood, or urine test. It is important to understand the implications of these tests and the consequences of refusal.

The Effects of Alcohol

Many people wonder how many alcoholic drinks they can have before they are considered “legally drunk." However, each person is unique in the way that their body reacts to consuming alcohol. There are many different factors that can affect your reaction to alcohol, including:

  • Height and body weight
  • Gender
  • Body fat percentage
  • Whether you recently ate
  • Dehydration
  • Medications and any medical conditions
  • Whether you also used drugs

Most states consider a person with a BAC of .08% legally intoxicated and unable to safely operate a motor vehicle. Utah has an even lower BAC limit of .05%. However, even with a BAC that is below the legal limit, you could still face a DUI or other criminal charges.

Alcoholic Drinks and BAC

When estimating how many drinks will put someone over the legal limit or a driver's BAC, one alcoholic drink typically consists of:

  • One 12-ounce of 5% ABV beer
  • One 5-ounce glass of 12% ABV wine
  • One 1.5-ounce shot of 80 proof (40% ABV) liquor

However, it is important to understand that not all drinks are the same. A lot of people having a beer get a 16-ounce craft beer that may have an alcohol level of 7% or higher. Some bars and restaurants offer wine in six- or nine-ounce glasses, with many wines having an ABV of about 14%. A single cocktail may include two or three shots of liquor.

Based on weight and sex, an average 180-pound person would likely be over the limit after only three drinks. Someone who weighs 140 pounds may be over the limit after two drinks. Over time, the body metabolizes alcohol, but the rate of metabolism also depends on a number of factors. This makes it difficult to come up with a standard rule for how many alcoholic beverages you can consume and how long you have to wait to drive.

Roadside Breathalyzer Tests

When a police officer pulls you over on suspicion of driving while intoxicated, the officer will typically request that you submit to field sobriety tests and/or a breath test. Officers use these tests to establish probable cause to make a DUI arrest. The breathalyzer or preliminary alcohol screening (PAS) device will give an estimated BAC. However, these breath tests may not be accurate, and there are false positives that can cause errors.

In most states, a roadside breath test is not mandatory. In those states, you have the right to refuse to participate in field sobriety tests and can refuse to submit to a roadside breath test. Some states, however, consider roadside breath tests to fall under their "implied consent" laws. If this is the case in your state, that means you have to take the roadside breath test or face a penalty like a driver's license suspension.

Some types of drivers may have to submit to a roadside breath test at all times. This includes drivers who are on probation for a DUI, underage drivers, or commercial vehicle drivers.

Test Refusal and Implied Consent Laws

States have implied consent laws that require drivers to submit to chemical testing when arrested on suspicion of DUI. Implied consent means that when you get a driver's license, you are agreeing to submit to a chemical test if police ever arrest you on suspicion of DUI. There are penalties for refusing a chemical breath test, blood draw, or urine test. Unlike with roadside tests, your refusal to submit to this test can be used as evidence against you in a civil or criminal case.

Consequences for refusal may include a mandatory license suspension. The suspension period may be the same or longer than the loss of your license for a DUI. Like a DUI, the license penalties may increase for subsequent drunk driving criminal or civil offenses or test refusals. Drivers can lose their license for up to a year for their first implied consent violation.

The breath testing equipment at the police station is supposed to be much more accurate, but there may still be problems.

A blood test can also show your BAC and test for the presence of drugs. A blood draw can happen at either the police station or a hospital. A lab will analyze your blood sample, and the results will show your BAC, as well as the presence of any controlled substances, including marijuana and some prescription medications. If you refuse to submit to a blood sample, the police can go to a judge for a warrant to take a blood sample against your will.

Challenging Chemical Test Result Evidence

If police do not follow proper chemical testing procedures, it may result in an inaccurate test result. Other problems with these chemical tests include:

  • Lack of proper calibration of the testing equipment
  • Failure to maintain the equipment
  • Contamination
  • Mixing up samples

If there is a problem with the chemical testing procedure, your defense attorney can file a motion to suppress the test results. If the prosecutor cannot rely on chemical test evidence to show your blood alcohol level was over the limit, they may have to drop your case, which may also allow you to avoid an automatic license suspension.