"[N]ine out of ten Californians believed the principle applied because Tarasoff was the law where they practiced. In contrast, less than one out of five in other locations believed Tarasoff, or a ruling like it, applied where they practiced. Most respondents seem to have a fairly good understanding of the jurisdictional issue, but a majority of them nonetheless believed themselves legally bound by Tarasoff. This inconsistency resulted from the belief that the Tarasoff ruling applied to their professions. One-half of the non-Californians thought Tarasoff applied to their professions. From a purely legal point of view this cannot be, because the California Supreme Court's authority is limited to lawsuits brought in California. The court has jurisdictional authority to establish rules governing cases brought before it, but it has no formal power to make rules which positively regulate professional practice everywhere. In the formal sense, then, the belief that the Tarasoff principle applies to professionals everywhere is incorrect.

Therapists may not have much interest in or understanding of such formalities. Rather, they may want to know what is likely to happen to them if they are sued in a local court. Few lawyers, however, would feel comfortable providing blanket assurances to therapists that a given court would not follow Tarasoff when the case has been neither officially adopted nor rejected outside California. Perhaps the most accurate description of the decision is that it is potentially the law everywhere. This uncertainty is disturbing to therapists seeking guidance. That non-California therapists are evenly divided on the question of whether they are legally bound by the Tarasoff decision probably reflects this general uncertainty.

Another feature ... merits attention: the degree to which therapists agree that the Tarasoff principle applies to them as a matter of personal and professional ethics. With the exception of California psychiatrists, at least 60% of each group considers responsibility to potential victims to be a professional ethical obligation, and at least three out of four of each group consider it to be a matter of personal ethics.

These figures certainly cast considerable doubt on the amici's argument that Tarasoff offends professional ethical mandates. However, the amicus brief criticized the duty to warn, whereas [the] respondents only endorsed the broader principle that a therapist has ethical responsibilities to protect potential victims. Nonetheless, the data certainly contradict the assertion that therapists must only concern themselves with the welfare of their patients and not with that of society at large. Moreover, since warning appears to be a primary technique for protecting potential victims, the endorsement of the general principle arguably represents an implicit endorsement of the narrower proposition that warning is ethically acceptable behavior. At the very least, [the] data suggest that the arguments that Tarasoff required deviation from ethical standards were considerably overstated. Alternatively, the pre-Tarasoff ethical standards had so tentative a hold over our respondents that within five years of the decision they have been swept aside in favor of a new ethical vision consistent with Tarasoff." [Daniel J. Givelbe, William J. Bowers and Carolyn L. Blitch, "Tarasoff, Myth And Reality: an Empirical Study of Private Law in Action," 1984 Wis. L. Rev. 443, 473-476].