Driving while intoxicated (DWI) is considered a crime across the states. If a person is suspected of a DWI, the law enforcement officer who is making the arrest needs to provide evidence in order to support DWI conviction. Aside from their own testimony, other evidence that they need to provide are the results of chemical tests. 

If you’re ever pulled over for suspicion of a DWI, it pays to know what to expect. In this article, we’ll be providing basic information when it comes to DWI chemical tests – from definition and types to their purposes and refusal to perform them. 

What is a DWI chemical test?

Commonly referred to as sobriety tests, chemical tests are a means of determining blood alcohol concentration (BAC) level. These tests are typically applied in situations where the law enforcement suspects individuals of drunk driving. 

A sobriety test or a chemical test is used to measure the amount of alcohol that is present in the driver’s system at the time of the arrest. There are different types of chemical tests that are performed, and they vary in terms of reliability. The results of these tests can then be used as evidence to support DWI conviction, along with the officer’s statement. 

What is the purpose of a DWI chemical test? 

The purpose of performing a chemical test is to determine whether the driver is illegally operating a vehicle while intoxicated. Given the drunk driving statistics and the alarming rate at which alcohol-related car accidents take place, improving and maintaining road safety is imperative. 

By detecting drunk drivers and removing them from the road, law enforcement can prevent a number of potential car crashes that end up in injuries or death. Even a small amount of alcohol present in the driver’s system can affect their driving abilities and reduce their coordination, concentration, and decision-making skills.

What are different DWI chemical test types? 

There are three different types of DWI chemical tests that are performed when determining the driver’s blood alcohol concentration (BAC) level. Blood tests, which are the most accurate ones, are tests that are performed by drawing blood from the subject. The blood sample is then sent for testing. 

The second type of chemical tests is urine test, during which the subject’s urine sample is analyzed to determine BAC level. Urine tests take a bit longer and require effort on both sides, and they are not the most reliable ones. Last but not least, breath tests are the third DWI chemical test used to determine the approximate amount of alcohol present in the subject’s blood. The portable instrument used to analyze a subject’s breath is called a breathalyzer, and when performed right, these types of tests are very reliable. 

Can I refuse a DWI chemical test? 

Due to implied consent laws that exist in most states, subjects are expected to undergo a sobriety test when asked to. According to these laws, any individual operating a vehicle is automatically agreeing to perform chemical tests in case they’re pulled over by a law enforcement officer. 

In case the subject refuses to perform the chemical test, they are not complying with the implied consent law, which can lead to penalties. The severity of the penalties will depend on the state, and while in some states you can have your license suspended, other states may also demand you pay a fine as well. 

Different ways of challenging DWI chemical tests 

For those charged with a DWI, challenging chemical tests is one of the strategies that can influence penalties and reduce their severity. While fairly reliable, chemical tests aren’t 100% accurate, and the results are often influenced by a variety of factors. 

From existing medical conditions to the use of certain medications, there are different circumstances that can lead to inaccurate results and, therefore, wrongful convictions. Other factors that can lead to unreliable results include improper administration of the sobriety tests and the time when they’re taken. Absence of a probable cause is another common defense strategy. When there is no reasonable ground for making a DWI arrest, the law enforcement officer is not allowed to perform the sobriety test. 

Beating a DWI charge by challenging chemical tests

Operating a vehicle while intoxicated is considered a crime in all states, although DWI laws are different across the states and the severity of DWI penalties may vary. Chemical testing is a common method for determining BAC levels, and although reliable, it isn’t always accurate. 

If you or a loved one is charged with a DWI, working with a reputable DWI lawyer is imperative. They can help you come up with the best defense for your case, navigate the legal system more easily while ensuring a favorable outcome for you as their client.