ABA Formal Opinion 512 vs. State Bar AI Rules

ABA Formal Opinion 512 issued in July 2024. It is the floor for attorney AI ethics in the United States. Six existing Model Rules duties get restated as applied to generative AI use. No new rules emerge. Existing Rule duties already required everything the opinion now spells out.

State bars that have ruled on the question after July 2024 mostly track ABA 512. A few have gone further. Where states diverge is predictable: disclosure to courts, billing for AI-assisted work, confidentiality of client data, supervision of AI vendors. This post reads the where-they-went-further axis. The structure follows ABA 512’s six duties.

A companion piece, the ABA Opinion 512 compliance guide, walks through what each rule says and includes a 12-item compliance checklist. This post assumes you know the rules in outline and want to know how they bind in your state. Multistate firms should read both.

Quick orientation: ABA 512’s six duties

Six Model Rules get restated. Under Rule 1.1, competence requires understanding the AI tools you use, including their limits and hallucination risk. Rule 1.6 confidentiality bars entering client information into AI tools that may train on or expose that data. Material AI use triggers a client-communication duty under Rule 1.4, with a fact-specific threshold. Billing an hour for ten minutes of AI-assisted work violates Rule 1.5 on reasonable fees. Partners and supervising lawyers carry Rules 5.1 and 5.3 supervision duties for subordinate and non-lawyer AI use. Verifying AI output is the lawyer’s duty under Rule 3.3 candor.

Disclosure to courts is not required by ABA 512 as a default rule. That question is left to local court rules.

State-by-state comparison: the formal opinions

Fifteen jurisdictions (14 states plus DC) had a formal AI ethics opinion in place as of 2026-05-09. They are listed below in approximate effective-date order. California is included for context as a sixteenth row even though its Practical Guidance is technically informal: in practice, California attorneys treat it as the operative standard, and the State Bar of California has open public comment on a Rule 1.0.1 amendment that would convert it to a binding rule.

Other states have informal guidance, working groups, or court-rule overlays that practicing attorneys must factor in. Examples: Illinois, New Jersey, and Michigan. The full 50-state-plus-DC matrix lives on the tracker index.

Where states went further than ABA 512

Disclosure and informed consent

ABA 512 leaves disclosure to local court rules. Florida’s Opinion 24-1 reads the client-communication duty (Rule 1.4) more aggressively. The opinion advises that informed consent is required when AI use is material to the representation, including any task that touches client confidential information or substantive legal analysis. The threshold is lower than ABA 512’s “fact-specific” framing.

Florida is the cleanest case for the proposition that a state has gone beyond ABA on client communication. New York City Bar Op 2024-5 lands close to Florida on confidentiality but stops short on disclosure: it advises informing the client when AI is material but does not impose an informed-consent requirement.

In court, the picture is more nuanced than a simple disclosure rule. New York’s 22 NYCRR Part 161 takes effect June 1, 2026. It sets a system-wide no-disclosure default. Lawyers and parties using AI in court papers are not required to disclose that use. Part 161 then authorizes individual courts to adopt an Appendix A Model Rule. Under the Model Rule, signing the paper certifies it contains no fabricated AI content. The certification regime is per-court, not statewide. A firm filing in NY needs to know which courts have adopted the Model Rule. Texas judges in SDTX and NDTX have issued individual standing orders that vary from disclosure to certification to outright prohibition. The court orders tracker lists 100+ such orders by judge. ABA 512 says nothing about these court rules. State bar opinions do not preempt them.

Billing and reasonable fees

ABA 512 restates Rule 1.5. A lawyer cannot bill the client an hour for ten minutes of AI-assisted work plus pretend it was an hour of human work. California’s Practical Guidance is more granular. Two specific instructions appear. First, do not charge for tool subscription fees as if those fees were billable time. Second, bill AI-generated work product at a rate reflecting the actual time spent on review and editing. The human-equivalent rate the document might command if drafted from scratch is not the right measure.

This is a real divergence. Imagine a California firm that bills four hours for AI-assisted research that took the supervising attorney 30 minutes to verify. That firm is exposed under California’s rule in a way ABA 512 does not directly address. The same firm in Texas, where Op 705 tracks ABA 512 closely on billing, has more latitude in framing.

Confidentiality and vendor diligence

Texas Op 705 has the most detailed factor test for confidentiality. Specific questions are enumerated. Does the tool retain inputs for training? Are outputs accessible to other users? Do the vendor’s terms of service permit secondary use? Is a non-disclosure or business-associate agreement in place? Op 705 also gives examples of tools that pass and fail the test. Most state opinions do not.

NYC Bar Op 2024-5 is comparable in detail. It adds a vendor-supervision frame: AI vendors are treated under Model Rule 5.3, the rule governing supervision of non-lawyer assistants. New Jersey’s Supreme Court Notice (Jan 2024) makes the 5.3 framing explicit. It ties supervision to a duty to verify the vendor’s data-handling policies.

The practical effect: a lawyer in Texas, New York, or New Jersey who pastes a client’s contract into ChatGPT without enabling enterprise privacy controls has a documented bar-rule problem, not just a best-practice problem.

Candor and verification

Every state opinion that has issued tracks ABA 512 on Rule 3.3. The duty to verify AI-cited authority is universal across the United States. The variation is on the consequence side, which lives in court orders and case law rather than bar opinions. The sanctions patterns post tracks the consequence layer.

Fee structure (Virginia’s deliberate departure)

Virginia LEO 1901 is the most distinctive divergence in the dataset. Its November 2025 approval by the Virginia Supreme Court was deliberate. Virginia expressly departs from ABA 512 (and from North Carolina 2024 FEO 1) on Rule 1.5 fees. Value-based and flat fees remain permissible even when AI dramatically reduces time spent on the work. Virginia attorneys are not required to reduce a flat fee solely because AI accelerated drafting. Verification duties are restated alongside this billing flexibility. There is no malpractice safe harbor for AI errors.

For a multistate firm, this is a real planning constraint. The same flat-fee engagement permissible in Virginia may not be permissible in California, which leans toward time-actually-spent under the Practical Guidance. Other jurisdictions following ABA 512’s implication that efficiency gains should flow to the client may also push back on a Virginia-style fee structure.

Supervision

Oregon Op 2025-205 treats firmwide AI use as a supervisory matter under Rule 5.1, with examples of what monitoring looks like in practice. NYC Bar Op 2024-5 and New Jersey Supreme Court Notice (Jan 2024) reach a comparable place via Rule 5.3, framing AI vendors as non-lawyer assistants that supervisory lawyers are responsible for vetting. ABA 512 covers the same territory but at a higher level of generality.

Where ABA 512 is the ceiling and not the floor

A handful of states have gone short of ABA 512, mostly by silence. Illinois has no formal bar opinion as of 2026-05-09. The Illinois Supreme Court issued an AI Policy in July 2024. That policy binds judicial-branch employees, not practicing attorneys filing in state court. ARDC has issued informal guidance. Otherwise, practicing attorneys in Illinois operate under the ABA Model Rules with no state-specific gloss.

States with no formal opinion and no court rule affecting representational practice include Wyoming, North Dakota, South Dakota, Vermont, and most other small-bar states. Multistate firms should not assume those states will remain quiet through 2026. The trend is toward formal opinions.

Multistate practice: cross-state risk

Take a firm with offices in California, New York, and Texas. Three distinct regimes apply:

• California’s Practical Guidance on billing
• New York’s NYC Bar Op 2024-5 confidentiality emphasis plus Part 161’s per-court certification overlay
• Texas’s Op 705 vendor-diligence factor test

The firm’s AI policy must satisfy the most restrictive rule across the three. In practice that means three things. Billing aligned to actual time spent (the California floor). Vendor diligence with documented contract review (the Texas floor). A per-court check at intake to identify whether each filing court in NY has adopted the Part 161 Appendix A Model Rule (which requires a certification, not a disclosure). A policy that satisfies any one of these states alone leaves gaps in the others.

For multistate firms, the Carrier-Renewal Packet annexes the policy to each state’s binding regime; for firms with operations in three or more states, consulting runs the gap analysis state by state.

What changes between now and 2026 year-end

Three live items to watch:

1. California Rule 1.0.1 amendments. Open public comment is underway on proposed amendments to Rule 1.0.1 that would explicitly address generative AI. If adopted, California moves from informal Practical Guidance to binding rule. Proposed amendment text and current public-comment status are on the California state page.
2. Multistate court rules. More federal districts and state courts are issuing standing orders. Aggregate counts live in the court orders tracker. Compliance with court rules is a separate sanction risk on top of bar duties.
3. Next batch of state opinions. Several state bars have working groups or proposed opinions in draft. Most active right now: Massachusetts, Washington, and Pennsylvania. Our state tracker updates as opinions issue.

A note on state divergence and bar enforcement

Bar enforcement of AI-related rules is uneven. Cases drawing bar discipline (rather than only court sanctions) are a small subset of the sanctions docket. States with the highest bar-discipline frequency are the same states that have published formal opinions. An opinion is the predicate that makes a complaint actionable.

Two factors matter when a firm assesses its risk. First, whether the firm’s home state has a formal opinion that names AI duties specifically. Second, whether the firm files in any court whose standing orders impose disclosure or verification on top of the bar rule. Both layers carry sanctions exposure. A clean record under the bar rule is not a defense if the court rule is what was violated.

This article is for informational purposes only and is not legal advice. State bar rules and court rules vary; consult a licensed attorney in your state for representation-specific questions. All citations are to primary sources; see the state tracker for the latest opinion text.