ABA Formal Opinion 512 on generative AI - a practical summary for lawyers
By LegiMatch Research Team · Published October 14, 2026 · 4 min read
Short answer: ABA Formal Opinion 512 (July 29, 2024) says lawyers may use generative AI, but the existing Model Rules apply in full. You must understand the tool well enough to use it competently, protect client information, tell clients when it matters, verify everything you file, supervise people and tools, and bill fairly for AI-assisted work.
Why the opinion matters
Opinion 512 is the American Bar Association's first formal ethics opinion devoted to generative AI. It isn't binding by itself - state rules and state bar opinions govern your license - but many state bars have issued guidance pointing in the same direction, and courts cite the same principles when sanctioning AI-related mistakes.
The six duties, in plain terms
| Model Rule | What the opinion expects | In practice |
|---|---|---|
| 1.1 Competence | Understand the tool's capabilities and limits; review its output | Know whether a tool can invent citations; read every authority |
| 1.6 Confidentiality | Assess the risk that client information is disclosed or reused | Check whether inputs are stored or used for training; get informed consent where required |
| 1.4 Communication | Tell clients about AI use when it's relevant to their decisions | Disclose when asked, when it affects fees, or when client data goes into a tool |
| 3.1, 3.3, 8.4(c) Candor and meritorious claims | Don't file anything inaccurate | Verify facts, law and quotations before filing |
| 5.1, 5.3 Supervision | Set policies for lawyers, staff and vendors | A written AI-use policy and training |
| 1.5 Fees | Bill reasonably for AI-assisted work | Don't bill hours the tool saved; disclose AI costs you pass on |
Competence: you don't need to be an engineer
The opinion asks for a "reasonable understanding" of the technology - enough to know what it does well and where it fails. For legal research that means knowing:
- whether the tool returns real, linked decisions or generates text that only looks like citations
- how current its library is, and which courts it covers
- that summaries and explanations can be wrong even when the citation is real
Confidentiality: the question to ask every vendor
The opinion distinguishes tools that keep or learn from what you enter ("self-learning" tools) from tools that don't. Before putting client information into a tool, find out:
- Is my input stored, and for how long?
- Is it used to train or improve models?
- Who at the vendor (and its subprocessors) can see it?
- Can I delete it?
If client information could be disclosed or reused, the opinion says informed client consent may be needed - and boilerplate in an engagement letter isn't enough.
Fees: the most practical part
- Hourly billing: bill the time you actually spent, including reviewing AI output - not the time the task would have taken without AI.
- Learning the tool: generally not billable to the client, unless the client asks you to use a specific tool.
- Tool costs: general software is overhead; a specific, identified tool cost may be passed through if the client agrees.
A checklist to adopt today
- A one-page firm AI policy: approved tools, what client data may be entered, verification steps
- Vendor answers on storage, training use, access and deletion, kept on file
- A verification step for every filing: open each authority, check quotes, check subsequent history
- Engagement-letter language explaining AI use and how it's billed
- Training for associates and staff, refreshed yearly
Frequently asked questions
Does ABA Formal Opinion 512 prohibit lawyers from using ChatGPT?
No. It allows generative AI tools, including general-purpose chatbots, as long as lawyers meet their existing duties of competence, confidentiality, communication, candor, supervision and reasonable fees.
Do I have to tell clients I used AI?
Not always. The opinion ties disclosure to Rule 1.4 and 1.5: tell clients when AI use affects their decisions, their fees, or when their confidential information goes into a tool that could disclose or reuse it - and always answer truthfully if asked.
Can I bill clients for time saved by AI?
No. Under hourly billing you charge for the time actually spent. Flat fees can remain reasonable if they reflect the value delivered, but the opinion warns against charging for efficiencies the client never received.
Is Opinion 512 binding in my state?
ABA opinions are persuasive, not binding. Your state's rules of professional conduct and state bar guidance control. Many states have issued AI guidance consistent with Opinion 512.
Sources
- ABA Standing Committee on Ethics and Professional Responsibility, Formal Opinion 512, "Generative Artificial Intelligence Tools" (July 29, 2024)
- ABA Model Rules of Professional Conduct 1.1, 1.4, 1.5, 1.6, 3.1, 3.3, 5.1, 5.3, 8.4
This article is general information about legal research, not legal advice. Verify every authority before relying on it.
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