Also known as:personal and substantial · personally substantially participated · personal and substantial participation
Written by attorneys · grounded in primary & secondary sources — see below
A standard of involvement that requires direct, hands-on participation by a lawyer in a discrete matter rather than peripheral or supervisory contact. The standard is met when the lawyer exercises independent judgment, makes strategic decisions, or commits resources on behalf of a client or agency in connection with a specific controversy involving identified parties.
Sources & Authorities
How it applies
Common Examples
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Former Agency Lawyer Switches Sides
Paul Peterson led an administrative prosecution for the state environmental agency against Prism Analytics for river contamination. After leaving the agency, Paul joined a private firm that Prism Analytics hired to defend the company in a civil suit brought by downstream homeowners over the same discharge. Because Paul personally directed the investigation, drafted the complaint, and appeared at the hearing, the rule bars him from representing Prism Analytics without the agency's informed written consent.
In-House Counsel Disqualification
Parker Phillips, while serving as in-house counsel at Premier Manufacturing, personally reviewed safety data and drafted internal reports on a product defect. After joining a new firm, Parker sought to represent a plaintiff suing Premier over the same defect. The court disqualified Parker because his prior work involved direct responsibility for the company's legal affairs on that precise issue, and the firm had not promptly screened him.
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Test Yourself
10
Practice Questions5
· 7 primary sources
Select any source to read its text and confirm it supports the definition.
Cases
Model Codes
Casebooks
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Study Supplements
Current Government Lawyer Barred
Piper Patel, now a lawyer at the National Drug Safety Agency, previously represented Helio Pharmaceuticals in private practice and helped draft its safety submissions for a prescription drug. The agency now asks Piper to participate in an enforcement review of the same drug. Because Piper participated personally and substantially in the matter while in private practice, the rule prohibits her involvement absent the agency's informed written consent.
Former Judge Representation Bar
Pavel Petrov served as a law clerk to a federal judge and personally drafted the order denying a motion to dismiss in a securities case involving Phoenix Technologies. After his clerkship, Pavel joined a firm that Phoenix Technologies retained to defend the same case. The rule bars Pavel from representing Phoenix Technologies because he participated personally and substantially in the matter as a law clerk, unless all parties give informed written consent.
Common questions
Frequently Asked
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What level of involvement satisfies the personally and substantially standard?+
Direct, hands-on work such as leading an investigation, drafting complaints or consent orders, interviewing witnesses, or appearing at hearings meets the standard. Mere supervisory oversight or peripheral review does not.
Supporting sources
Does the same-matter requirement turn on whether the later case involves the identical plaintiff or remedy?+
No. The rule focuses on the underlying controversy, parties, and facts. An administrative enforcement action and a later private damages suit arising from the same conduct constitute the same matter even when the plaintiffs and requested relief differ.
Supporting sources
When may a firm continue representation after a personally disqualified former government lawyer joins?+
The firm may proceed only if it timely screens the disqualified lawyer from the matter, apportions the lawyer no part of the fee, and provides prompt written notice to the affected agency so that compliance can be verified.
Supporting sources
Does screening cure the conflict for the personally disqualified lawyer herself?+
No. Screening protects the firm and its other lawyers but does not permit the individually disqualified lawyer to participate in the representation without informed written consent from the appropriate agency.
Supporting sources
Professional ResponsibilityConflicts of interest · Lawyers currently or formerly in government serviceMPREFoundational