What Is an AI Second Opinion — and When Do You Need One?

Definition

An AI second opinion is the review of AI-generated work — a contract, a tax return, financial statements, any consequential document — by a licensed human professional who verifies it against your actual situation and jurisdiction, and signs off on the result. The AI does the drafting. The professional supplies the two things a model cannot: judgment about your specific facts, and accountability for the conclusion.

Why this practice exists

Three things collided in the mid-2020s. First, AI drafting became genuinely good — good enough that millions of people now generate contracts, tax filings, and business documents that would have cost thousands of dollars a few years earlier. Second, AI's failure modes turned out to be systematic and well documented: invented citations, outdated law, jurisdiction blending, confident errors (see what AI gets wrong in legal documents). Third — and decisively — regulators responded by mandating human verification. The American Bar Association's Formal Opinion 512 requires lawyers to verify AI output before relying on it; California's bar proposed rules requiring verification of every AI output a lawyer uses. The professions institutionalized a rule the rest of us can borrow: use the machine, verify with a human who answers for the result.

The key insight: the signature is the product

Ask why you can't just have a second AI check the first AI — it's a fair question, and running one is actually a decent way to find issues worth asking about. But in consequential domains, verification isn't only error-hunting. It's accountability. A licensed attorney, CPA, or enrolled agent who signs off stakes their license, their professional insurance, and their standing on that judgment — and can represent you when the document is challenged. No AI can hold a license, carry malpractice insurance, or answer to a regulator. That's not a temporary technical limitation; it's what "licensed" means. However good models get, the sign-off remains something only a human professional can sell — which is why the sensible division of labor is stable: AI does the work; a professional signs the work.

What an AI second opinion covers, by field

The decision rule

You don't need a second opinion on everything — that would waste the savings AI created. The test we use across this site: imagine the AI-generated document fails completely. If that outcome would genuinely hurt you — money, property, rights, taxes, liability — get it reviewed and signed by a licensed professional before you rely on it. If you could shrug it off, the AI draft alone is proportionate. Most documents in most lives fall on the shrug side. The ones that don't are exactly the ones this practice — and this directory — exist for.

Get it signed by a pro

SignedByPro is a directory of licensed professionals who review AI-generated drafts — contracts, tax returns, financial statements — and sign off on them. Launching soon.