“Implied consent” is the law in California. Implied consent means that a driver in this state is required to submit to a breath, blood, or urine test – after being arrested for DUI – if a law enforcement officer has probable cause to believe that the driver has been driving while under the influence of alcohol or drugs. Every year, almost 200,000 California motorists are convicted of driving under the influence (DUI). Most of those convictions are based on DUI breath test results. This is where a DUI attorney can help.


When anyone applies to receive a driver’s license in the state of California, the law presumes that the driver will agree to submit to a breath, blood, or urine test if he or she is arrested for driving under the influence. If a driver’s license was not issued in California, simply driving on any California street or highway means that the driver implies his or her consent to be tested after a DUI arrest.


When a driver in California is stopped by a law enforcement officer and the officer conducts a DUI investigation, the officer may ask the driver to blow into a portable breathalyzer device called a Preliminary Alcohol Screening (PAS) machine. California drivers have the legal right to decline this test (with two exceptions that are listed below). California law requires the officer to advise the driver that the PAS test is voluntary and that the driver has the right to decline it. Technically speaking, a driver in California does not have to take any DUI test before or until being formally taken into custody, with these two exceptions:

  • If a driver is under 21 years of age, that driver must blow into a breath-testing device if a police officer requests it, or the driver could forfeit his or her driving privilege for a year.
  • If a driver is on probation for a previous DUI conviction, that driver must also blow into a breath-testing device if a law enforcement officer requests it. One term of probation is that a convicted DUI offender may not drive with any measurable blood alcohol content level. If a driver has a prior DUI conviction and refuses to submit to a breath test, he or she could lose the privilege to drive for a year, along with being penalized for violating the terms of probation.

For all other drivers in California, implied consent only means that the driver must submit to a test if he or she is asked after being arrested. However, if a driver refuses to submit to a preliminary test before an arrest, and if the police officer has reason to believe that driver has been drinking or using drugs, the officer can make a DUI arrest, and the driver will then be required to take the test. In fact, refusal to test can be considered “evidence” of guilt and give an officer just to make the arrest.

A DUI test must be administered at the time of the driver’s arrest. When any motorist is arrested by a California law enforcement officer for suspicion of driving under the influence, that motorist has the right to choose between a blood test and a breath test for blood alcohol content. Alternately, if drugs are suspected as the reason for a driver’s impairment, the choice will be offered between a blood test or a urine test.

Law Enforcement Officer

A driver probably should not refuse or resist testing, either before or after an arrest. There are specific legal penalties for refusing to test after a formal arrest, and if a driver does not cooperate, he or she could conceivably face additional criminal charges. In most cases, for most drivers, it is probably better to submit graciously to the test. In southern California, an experienced Los Angeles DUI attorney can challenge the test results later on the driver’s behalf. California law does have an exemption for drivers who are taking anticoagulants for a heart condition and for drivers with hemophilia – they do not have to take a blood test.


When a California law enforcement officer asks a driver to submit to a DUI test, the officer must explain that any refusal to test means the driver will be fined, will lose his or her driver’s license, and could be sent to jail if later convicted of driving under the influence. A driver charged with DUI does not have the right to speak to a DUI attorney about whether to take the DUI test, and the officer should explain that.

Police Officer

The right to have an attorney present kicks in only when a suspect is being interrogated, but it does not apply if a suspect is only being tested for driving under the influence. A refusal to test can be explicit – directly refusing to take the test – or it can be implied – for example, if the suspect simply remains silent or “goes limp.” It is also considered a refusal if a suspect fails to complete a test after first agreeing to it.


In California, the minimum penalty for refusing to submit to a DUI test is a one-year driver’s license suspension. For a second refusal, the penalty is a two-year suspension, and for a third refusal, the penalty is a three-year driver’s license suspension. The fine for refusal to test is the same – $125 – whether it is a first, second, or third refusal. Any California driver seeking to learn more about DUI testing or DUI laws in this state should contact an experienced Los Angeles criminal defense attorney for more information.

If you are stopped while driving for suspicion of DUI, politely refuse to answer any questions a police officer may ask. After presenting your license and registration, you can simply say that you prefer to exercise your right to remain silent. If you’ve actually had a drink, don’t deny it; just say that you prefer not to answer any questions without a DUI attorney present. In the end, the decision to test for DUI or to refuse the test is up to you. What’s important is that you know your rights and that you are able to make a fully-informed decision.