"If I don't agree to do field sobriety tests, is this "consciousness of guilt" of a California DUI?"

California DUI FST's are voluntary.

There is no statute requiring a person -suspected of a California DUI - to perform field sobriety tests.

Even a person suspected of committing a California DUI has a constitutional right to remain silent and not to incriminate himself or herself.

It is not "consciousness of guilt" for a person to refuse to perform voluntary field sobriety tests offered by a California DUI police officer who suspects the person of driving drunk .

But exercising the right to not perform FST's may be considered by the California DUI police officer in determining whether or not he or she has probable cause to arrest a person suspected of a California DUI .

Refusal to submit to the required chemical test (blood or implied consent breath test) is something different. That can be a statutory refusal and may be considered as consciousness of guilt, if the facts so warrant. [A driver arrested for a California DUI may have a good reason for refusal to submit to a chemical test e.g. officer-induced confusion, or interference with the person's ability to hear & understand the officer's required chemical test refusal admonition.]

Marvin v. DMV (1984) 161 CA 3d 717, 720, a DMV case containing dicta often misrepresented by a California DUI prosecutor who may have failed to read the entire case, states in pertinent part:

"In the course of his continued investigation, it was reasonable for the officer to seek a field sobriety test of the drunken driver suspect. And when the suspect, plaintiff Marvin, refused the field sobriety test, additional evidence of her guilt appeared. Such has been held to be evidence of a consciousness of guilt.

In People v. McGinnis (1953) 123 CA2d Supp. 945 [267 P2d 458], the court was also concerned with the refusal of a suspected drunken driver to submit to a sobriety test. It was concluded that such a refusal was conduct tending to show a consciousness of guilt, and that it was therefore admissible in evidence against the suspect. (To the same effect see People v. Zavala (1966) 239 CA2d 732, 740-741 [49 CR 129]; People v. Conterno (1959) 170 CA2d Supp. 817, 831 [339 P2d 968]; Witkin, Cal. Evidence (2d ed. 1966) The Hearsay Rule, § 515(e), p. 485.)

In the case before us the officer had observed plaintiff Marvin's erratic driving, he then detected a strong odor of alcohol about her breath and person. And when, added to that evidence, was her refusal to submit to a field sobriety test, reasonably interpreted as a consciousness of guilt, there was patently probable cause for her arrest.

It becomes the function of this court on the uncontroverted evidence to determine, in light of the whole record, whether there is substantial evidence tending to support the finding of the superior court, and in considering this question we must view the evidence most favorably to the finding. ( In re Roderick P. (1972) 7 Cal.3d 801, 808 [103 Cal.Rptr. 425, 500 P.2d 1]; People v. Johnson (1980) 26 Cal.3d 557, 576-577 [162 Cal.Rptr. 431, 606 P.2d 738, 16 A.L.R.4th 1255].) Applying this rule, we find no substantial evidence supportive of the superior court's finding of a lack of probable cause for plaintiff Marvin's arrest.

It becomes unnecessary to determine whether probable cause for plaintiff's arrest existed before her refusal to take the sobriety test."

In these case, there is no reference to the voluntary nature of FST’s, nor of one’s constitutional right to remain silent when in the custody of the California DUI police, merely consciousness of guilt when one declines the California DUI police directive to perform California FST’s.

These two ancient cases merely contain dicta indicating that a legal position of consciousness of guilt based on failure to perform FST's may be tenable.

A California DUI police officer should admit: (a) that there is no California Vehicle Code section that requires field sobriety tests, (b) that there is no California Penal Code section that requires Fst's, (c) that there is no law that requires a person to do FST's, and (d) if heaven forbid the officer would be suspected of a California DUI, the officer could exercise his right to not perform these acrobatics or gymnastics.