To warn and to control: two distinct legal obligations or variations of a single duty to protect?

Prior to the Tarasoff decisions, jurisprudence pertaining to the duty to warn, or inform, to prevent violence to third persons, was separate from that pertaining to the duty to control to prevent such violence. The Tarasoff Principle consolidated preventive obligations in the face of foreseeable violence under a single "duty to protect." Even as courts adopted divergent rules for establishing foreseeability, many held to a single duty to protect with warnings as one possibility for fulfilling this option. Particularly over the past decade, courts have again disengaged the duty to warn and the duty to control, each requiring different legal predicates to occur. In recent years, courts have upheld or rejected a duty to warn, upheld or rejected a duty to control; and several courts have, within a single opinion, articulated fundamental distinctions between these two separate protective duties.