Can I refuse to take a roadside breath test or other field sobriety tests?
You do have the option of refusing to take a roadside sobriety test, but each individual situation and type of test requested will yield different results; and whether or not it's a good idea to refuse will depend on these factors. A "roadside breath test," also called a preliminary alcohol screening test or "PAS," indicates the presence and/or concentration of alcohol based on a breath sample. You will be asked to blow into a breath meter. The purpose in giving this test is to determine if there is enough reasonable cause to arrest you for a DUI (driving under the influence). The PAS is not nearly as reliable as the Breathalyzer, and is usually not admissible in court. Defense toxicologists, will often state that the PAS is only useful to determine the presence of alcohol, not the quantity.
While you generally may refuse to take the roadside breath test, your refusal may not stop the officer from arresting you if there is other evidence of alcohol usage that would affect your ability to drive (e.g., slurred speech, bloodshot eyes, clumsiness, poor driving observed). Unlike the chemical test, where refusal to submit may have serious consequences, in most states you are not legally required to take any field sobriety tests or FSTs. However, keep in mind that your refusal may suggest to the officer that you have something to hide and incite further examination of whether or not you have been drinking.
The reality is that officers have usually made up their minds to arrest when they give the FSTs; and the tests simply provide additional evidence. In many cases, the suspect inevitably "fails" the field sobriety tests. However, officers are likely to testify that the FSTs were administered to help determine whether you were under the influence. This is because they don’t want to have to testify that during questioning, you were not free to leave (ie, “under arrest”). If you were under arrest, they would have been required to advise you of your Miranda rights even to ask you if you were drinking, and they don’t want to do that as it suggests to the suspect that they should stop talking--and thus, making it harder for the officer to determine if they are intoxicated. So, if the officer testifies that he asked you to do the FSTs because he was not sure you were under the influence, and you refuse the FSTs, that can build “reasonable doubt” into your case. The blood-alcohol test (BAC) is, however, another issue.
Obviously if you appear drunk in a videotaped field sobriety test, it will not impress the judge or jury. Thus, in most DUI cases a polite refusal "until I speak with an attorney" may be the most appropriate choice. Since the “pass” or “fail” on a field sobriety test is purely subjective, with no published standards for “passing”, you have little chance of helping your situation by taking the field sobriety test.