Field Sobriety Testing (FST) administration or refusal is one of the thorniest issues any DUI suspect faces. One must balance submitting to the tests against the introduction of "consciousness of guilt" evidence if one refuses. My advice to clients is to take the tests only if the instruction phase and the actual test phase are recorded on video. Given the prevalence of smart phones capable of capturing high quality audio and video this should not be a problem. In addition to asking the investigating officer if the tests are mandatory (which they are not, but the question should always be asked), the driver should also ask for the entire SFST/FST process to be video recorded. If the officer refuses the request, then the driver should decline to take the tests. It may be necessary for someone other than the officer to record the video (e.g. a passenger with his/her personal cellphone.) Absent some documented record capable of objective review, the tests become almost entirely subjective.  In Johnson County, most police cruisers have cameras installed and are utilized by most officers.  Generally, the video assists the officer and prosecutor in preparation for trial.  It is my experience the videos generally do not help the defense.  On occasion, however, the video confirms the client's version of events and can lead to dismissal or acquittal of DUI.