MBE Rules · Professional Responsibility
Lawyer as Witness
Cal. Rule 3.7
The rule
A lawyer may not act as trial advocate when likely to be a necessary witness, absent client informed written consent (California) or hardship exceptions; the disqualification is personal, not firm-wide.
In plain English
A lawyer cannot represent a client in a trial if they are likely to be a key witness in that case, unless the client gives informed written consent or there are exceptional circumstances. This rule applies to the individual lawyer and does not extend to their entire law firm.
Worked example
Attorney Smith is representing a client in a personal injury case where he was the only witness to the accident. Smith realizes he will need to testify about what he saw. Since he is likely to be a necessary witness, he must obtain the client's informed written consent to continue representing them, or he must withdraw from the case.
Memory hook
No dual roles: a lawyer can't be both advocate and witness without consent!
The trap
Exams may present scenarios where a lawyer is both a witness and an advocate, but students often overlook the need for client consent or the hardship exceptions. They might also confuse personal disqualification with firm-wide disqualification.
How examiners test it
This rule often appears in questions that involve a lawyer's potential testimony in a case, testing candidates on the implications of dual roles and the necessity of client consent.
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More Professional Responsibility rules
- Duty of Confidentiality · Cal. Bus. & Prof. Code § 6068(e); Rule 1.6
- Client Trust Account — IOLTA · Cal. Rules of Prof. Conduct 1.15
- Duty to Report Misconduct · Cal. Rules of Prof. Conduct 8.3
- Unconscionable Fees · Cal. Rule 1.5
- Fee Division Among Lawyers · Cal. Rule 1.5.1
- Compensation from Third Parties · Cal. Rule 1.8.6