In California, if you are pulled over in traffic by the police for suspicion of driving under the influence, are you required to take a field sobriety test (FST)? What about a breath test?

If you refuse to test, what are the consequences? These questions are complicated because the law that governs DUI testing in this state is complicated.

In all fifty states, if a police officer stops a motorist in traffic, and that officer reasonably believes that the motorist was driving under the influence of alcohol or drugs, the police officer will ask the motorist to perform one or more field sobriety tests.

An FST performance that tends to confirm the police officer’s reasonable belief will usually be followed by a breath test.


California’s “implied consent” law obligates drivers who have been lawfully arrested for DUI to submit to a chemical test to measure the blood alcohol content (BAC) level in that driver’s bloodstream.

A driver placed under arrest can usually choose either a blood test or a breath test, but if neither is available to the arresting officer(s), or if the driver has a medical condition that prevents blood testing, a urine test may be required.

The term “lawfully arrested” is critically important here, because if you have not yet been arrested, California drivers – with the exception of drivers who are under age 21 and drivers who are currently on probation for DUI – are not required to take a field sobriety or breath test.

And that’s where the legal complications begin for California motorists who are suspected of driving under the influence.

If you’ve already been stopped for suspicion of DUI, a police officer will be looking for probable cause to make an arrest. If you fail a preliminary breath test, that failure gives the police probable cause to arrest you.

But if you refuse to test, your refusal may also be considered probable cause, you will probably be arrested anyway, and then you are legally required to take a DUI test.


In California, when you are in police custody and asked to test for DUI, the law requires the police to explain the penalties for refusing to test after a lawful arrest. Refusing a breath, blood, or urine test after a DUI arrest can trigger a one-year driver’s license suspension.

The police must also explain that you have no right to speak to a lawyer before testing and that a test refusal can be used as evidence against you in a court of law.

Penalties for the refusal to take a breath, blood, or urine test after a lawful arrest for driving under the influence start with the one-year driver’s license suspension.

A second refusal is penalized with a two-year suspension, and a third refusal to test can be penalized with a three-year license suspension. There is also a fine – it’s $125 – whether it’s your first, second, or third refusal to test for DUI.

Refusal to test does not necessarily help you to avoid a DUI conviction in California. You can be found guilty of driving under the influence in this state without any DUI test results whatsoever.

The state can even allege that your refusal to test was based on your knowledge of your guilt – that you refused to test because you knew that you were intoxicated and you would fail the test.


But even if a test result shows that a driver is above the legal limit for driving under the influence – that is, the driver’s BAC level measures at or above 0.08 percent – is that test result accurate? Not always.

The most accurate DUI test is the blood test, but if a blood sample is not handled or preserved properly, or if the blood sample becomes contaminated, it can give a false reading.

In such cases, when a lab that conducts blood testing has not adhered to proper procedures, a good Orange County DUI defense attorney can cast doubt on the test results or even have those results tossed out of court.

However, motorists in California should understand that in most DUI cases, blood test results are deemed “accurate enough” to be introduced as evidence, and in most cases, those results are in fact considered conclusive evidence.

Breathalyzer results, like blood test results, can be wrong for a lot of reasons. Inaccurate results are likely when drivers have medical conditions like diabetes, hypoglycemia, and gastroesophageal reflux disease (GERD).

Breathalyzers must be routinely calibrated and maintained. Police officers must be trained to administer breathalyzer tests legally and according to standard procedures.


However, in most DUI cases, a blood or breath test will, in fact, provide the police with a relatively reliable assessment of a driver’s level of intoxication.

DUI is a serious crime in California, so anyone charged with DUI must have an experienced Orange County DUI defense attorney working on his or her behalf.

These are the penalties a misdemeanor, first-offense DUI conviction in this state:

– a fine from $390 to $1000
– court-related fees and assessments that in some cases can total as much as $2,600
– as much as six months in a county jail
– a driver’s license suspension lasting six months
– probation for three to five years

In Los Angeles, Alameda, Sacramento, and Tulare counties – and statewide beginning in 2019 – all convicted DUI offenders will be required to install an ignition interlock device or “IID” in their personal vehicles.

There is also a restoration fee when the driver’s license suspension is lifted and a requirement for offenders to receive treatment or attend DUI classes – and pay for them.

Of course, the simplest way to avoid being tested, arrested, or prosecuted for driving under the influence is something you’ve heard before – Don’t Drink and Drive.

Especially in southern California, there is an abundance of rides-for-hire – taxis, limos, and Uber, for example – and most ride services are available 24 hours a day every day.

But legal help is also available if you need it, and if you are charged with driving under the influence in southern California, you will.