Duty to warn means telling a potential victim about a client's threat. Duty to protect is broader: taking reasonable steps to protect an identifiable person from a client's threatened violence, which can mean warning that person, notifying the police, or other steps such as arranging hospitalization. Both trace back to one California case, Tarasoff, and most states now have a law that either requires or permits action.
For the ASWB exam, the state law matters less than the order of events. The exam tests whether you assess a threat before you act on it, and whether you act when the threat is real. This is how the law got here, how it differs from state to state, and how the questions are built.
This post explains how a licensing exam tests the topic. It is not legal advice. If someone is in immediate danger, call 911.
What Tarasoff actually decided
On October 27, 1969, Prosenjit Poddar killed Tatiana Tarasoff. Two months earlier, according to the case, he had told Dr. Lawrence Moore, a psychologist at the University of California, Berkeley's Cowell Memorial Hospital, that he intended to kill her. Campus police briefly detained Poddar at Moore's request and released him when he appeared rational. In the court's words, "No one warned plaintiffs of Tatiana's peril": the plaintiffs were her parents.
Her parents sued, and on July 1, 1976 the California Supreme Court held:
When a therapist determines, or pursuant to the standards of his profession should determine, that his patient presents a serious danger of violence to another, he incurs an obligation to use reasonable care to protect the intended victim against such danger.
The court went on to list how that obligation can be met. It "may call for him to warn the intended victim or others likely to apprise the victim of the danger, to notify the police, or to take whatever other steps are reasonably necessary under the circumstances." And it explained why confidentiality gives way: "The protective privilege ends where the public peril begins."
So the case remembered as the duty-to-warn case actually set a duty to protect. Warning is one way to meet it, not the only one.
Warn, protect, report: three different duties
These get blurred together, on exams and in practice:
| Duty | What triggers it | What it asks of you |
|---|---|---|
| Duty to warn | A threat against an identifiable person, where state law requires or permits warning | Tell the person at risk, or someone who can tell them |
| Duty to protect | A serious danger of violence to an identifiable victim | Reasonable steps to protect them: warning, notifying police, or other steps such as hospitalization |
| Duty to report | Suspected abuse or neglect of a child, and in many states of an older or dependent adult | Report to the agency the law designates, usually without first confirming the abuse |
The 2026 ASWB outlines treat these as one family: duty to warn is named as an example inside the statement on mandatory reporting, together with abuse, threats of harm and impaired professionals, which our chapter on ethical service delivery covers. The confidentiality statement, which covers the limits of confidentiality, sits beside it. Our free lesson on confidentiality works through both.
State law: mandatory, permissive, or none
Tarasoff bound California, but it prompted "duty to warn" or "duty to protect" laws in almost every state, in the words of the National Conference of State Legislatures. NCSL's state survey, last updated March 16, 2022, sorts the 50 states and the District of Columbia like this:
| NCSL category | Count | Examples |
|---|---|---|
| Mandatory duty to protect or warn | 28 states | California, New York, Pennsylvania, Massachusetts, Michigan |
| Permissive: may disclose, not required | DC and 18 states | Texas, Florida, Illinois, Connecticut, Oregon |
| No duty | 3 states | Maine, North Carolina, North Dakota |
| Other | 1 state | Georgia, where a duty to protect arises in narrow circumstances |
Three examples show how different the rules are:
- California now writes the duty into its Civil Code. A psychotherapist is liable only if the patient "communicated to the psychotherapist a serious threat of physical violence against a reasonably identifiable victim or victims," and discharges the duty "by making reasonable efforts to communicate the threat to the victim or victims and to a law enforcement agency" (section 43.92). A 2013 amendment renamed it from a duty to warn and protect to a duty to protect, and the statute says that was a change of name, not substance.
- New York moved from a permissive to a mandatory duty in January 2013. NCSL describes the change as requiring mental health professionals to report when they believe a patient may pose a danger to themselves or others.
- Texas went the other way. In Thapar v. Zezulka (1999), the Texas Supreme Court declined to create a common-law duty for mental health professionals to warn third parties, and NCSL classes Texas as permissive.
NCSL's survey is the most complete public summary, but it is from 2022, and states amend these laws. If you practice, your state's current statute and your agency's policy are what bind you, not a survey and not this post.
What the NASW Code says
The NASW Code of Ethics reaches the same place from the ethical side. Standard 1.07(c) says the general expectation of confidentiality does not apply when disclosure is necessary to prevent serious, foreseeable and imminent harm to a client or to others, and it asks social workers to disclose only the minimum information necessary for that purpose. Standard 1.07(d) adds that clients should be told about a disclosure and its likely consequences, where possible before it is made.
Read together, the Code and the law describe a narrow gate: a real, specific danger opens it, and only as much information as protection requires goes through.
How the ASWB exam tests it
An exam taken in every state cannot ask what one state's statute requires, so the questions test the sequence instead. Confidentiality and its limits sit in Values and Ethics, the largest content area on every ASWB exam (what that area holds). ASWB's Guidebook shows this in one of its own sample questions, labeled REASONING, its highest cognitive level. An adolescent in an emergency department after a dog bite reveals, during a mental status exam, cruelty to the dog and internal commands to hurt a teacher. ASWB's keyed FIRST step is to assess whether there is a specific plan to harm the teacher. Its rationale says the social worker "must FIRST assess whether there is a specific plan," and only after that is it reasonable to find out whether the teacher or the parents know.
That is the first half of the rule: assess before you disclose. The second half is the one candidates forget: once the threat is real, act. Here is a question built on that second half.
A client in outpatient treatment tells a social worker, calmly, that the client has bought a handgun and intends to shoot a former business partner, whom the client names, on Friday evening, when the partner closes the shop alone. What should the social worker do FIRST?
- A. Explore the client's feelings about the business dispute.
- B. Take steps to protect the named person, following state law and agency policy.
- C. Ask the client to promise not to harm the former partner.
- D. Schedule an additional session before Friday.
B. The assessment is already in the stem: a named person, a weapon the client owns, a plan, a time and a place. Exploring feelings (A) is the right instinct for a vague threat and the wrong one here. A promise (C) is not protection. An extra session (D) delays action until after a danger the social worker already knows about. What protection looks like (warning the person, notifying the police, arranging hospitalization) depends on the state and the setting, which is why the option says so instead of naming one. Consultation and documentation follow, and the client is told what is being done where that is safe.
Put the two questions side by side and the rule is complete: a threat that has not been assessed calls for assessment, and a threat that has been assessed and is serious calls for protective action. Our ethics questions with worked rationales include a vaguer threat, where assessment is the right first step, and how the exam tests suicide risk applies the same sequence to harm to self.
The traps in these questions
- Warning before assessing. Disclosing on an ambiguous statement breaches confidentiality without a reason the law or the Code would accept.
- Assessing forever. Once the danger is specific and serious, more exploration is a delay.
- Promising absolute confidentiality. Informed consent includes the limits. A social worker who told a client at intake that everything stays private has a harder conversation later.
- Mixing up the duties. A duty to report suspected child abuse does not wait for proof, and it does not depend on a threat. A duty to protect does depend on one.
- Disclosing more than necessary. Protecting someone requires the threat, not the client's history.
If you are facing this in practice
Talk to your supervisor, read your agency's policy, and find your state's statute. If you carry professional liability insurance, its risk-management service is worth a call. If anyone is in immediate danger, call 911. And document what you assessed, who you consulted and what you did, as you do it.
Sources, read October 15, 2026: Tarasoff v. Regents of the University of California, 17 Cal. 3d 425 (1976), via Justia; California Civil Code section 43.92, via the California Legislative Information site; the National Conference of State Legislatures' "Mental Health Professionals' Duty to Warn" (updated March 16, 2022); Thapar v. Zezulka (Tex. 1999); the NASW Code of Ethics (2021); and ASWB's Examination Guidebook (August 2026). This is not legal advice. ASWB Master is independent and is not affiliated with, endorsed by, sponsored by or approved by the Association of Social Work Boards.