Medicare's WISeR AI prior-auth model still binds your claims while Congress moves to repeal it

WISeR is still running in six states, and if you bill one of its listed services there, your claims still go through prior authorization or pre-payment review. That didn't change on May 12, 2026, when the Government Accountability Office concluded that the notice CMS used to launch the Wasteful and Inappropriate Services Reduction (WISeR) Model is a rule for purposes of the Congressional Review Act. It didn't change a week later, when Senator Ron Wyden introduced a joint resolution to repeal it. Neither event stopped the model.

What the GAO decision actually says

GAO's decision (B-337994) answers one narrow question: is the WISeR Model Notice a "rule" under the Congressional Review Act? GAO concluded it is. The notice, GAO wrote, "prescribes new requirements for Original Medicare providers in selected states by mandating prior authorization or pre-payment medical review of claims for certain services," and therefore "substantially affects the rights and obligations of non-agency parties."

HHS had told GAO it didn't submit the notice because it considered the notice a guidance document, and that the CRA doesn't reach guidance. GAO rejected that reading, pointing to its own prior decisions holding that guidance, including guidance an agency calls non-binding, can still be a rule under the CRA.

What the decision doesn't do is invalidate the model or order CMS to stop. GAO decisions of this kind are legal opinions that open a procedural door for Congress. The model keeps operating while that door is open.

Where WISeR applies, and to which services

CMS describes WISeR as a six-year model running from January 1, 2026 through December 31, 2031 in Arizona, New Jersey, Ohio, Oklahoma, Texas, and Washington. Six technology companies serve as the model participants, each covering a state and a MAC jurisdiction; CMS says they applied through a Request for Applications. For a provider there is no opt-out of review itself. If you furnish a listed service in a listed state, either prior authorization or pre-payment review applies.

The July 1, 2025 notice (90 FR 28749) named 15 service families, each tied to an existing national or local coverage determination:

• Electrical Nerve Stimulators (NCD 160.7)
• Sacral Nerve Stimulation for Urinary Incontinence (NCD 230.18)
• Phrenic Nerve Stimulator (NCD 160.19)
• Deep Brain Stimulation for Essential Tremor and Parkinson's Disease (NCD 160.24)
• Vagus Nerve Stimulation (NCD 160.18)
• Induced Lesions of Nerve Tracts (NCD 160.1)
• Epidural Steroid Injections for Pain Management, excluding facet joint injections
• Percutaneous Vertebral Augmentation for Vertebral Compression Fracture
• Cervical Fusion
• Arthroscopic Lavage and Arthroscopic Debridement for the Osteoarthritic Knee (NCD 150.9)
• Hypoglossal Nerve Stimulation for Obstructive Sleep Apnea
• Incontinence Control Devices (NCD 230.10)
• Diagnosis and Treatment of Impotence (NCD 230.4)
• Percutaneous Image-Guided Lumbar Decompression for Spinal Stenosis (NCD 150.13)
• Skin and Tissue Substitutes, only in MAC jurisdictions and states with an active LCD

CMS excluded inpatient-only services, emergency services, and anything that would pose substantial risk to a patient if delayed. On April 6, 2026, CMS delayed two of the 15 "to allow additional time for operational readiness": Deep Brain Stimulation for Essential Tremor and Parkinson's Disease (NCD 160.24), and Percutaneous Image-Guided Lumbar Decompression for Spinal Stenosis (NCD 150.13). For those two, neither prior authorization nor pre-payment review is available right now. That leaves 13 in scope, and CMS says it may add services in future years.

Prior authorization or pre-payment review, your practice picks one

WISeR doesn't force a prior authorization request on you. It gives your practice two doors, and you walk through one of them whether or not you choose deliberately. Deciding by default is how a practice ends up assembling coverage documentation after the service instead of before it.

The criteria are the same on both paths. What changes is whether you find out before or after you've incurred the cost of the procedure. For a practice with thin cash reserves, that's the whole decision.

Where a human clinician is still required

WISeR is the first CMS Innovation Center model in which technology companies are the only participants, and CMS is candid that they apply "enhanced technologies, such as Artificial Intelligence (AI) and Machine Learning (ML), along with human clinical review."

The line that matters for anyone assembling documentation sits on CMS's own model page: "All recommendations for non-payment are determined by appropriately licensed clinicians who will apply standardized, transparent and evidence-based procedures to their review." CMS describes the technology as working alongside human clinical review. A clinician is who recommends that a service not be paid.

That has a practical consequence. The reviewer is a person reading your documentation against a coverage policy that already existed and is already public. Nothing about the model changes what the NCD or LCD requires. It changes when someone reads your chart against it, and how quickly. The lever a coder or biller actually controls is whether the record speaks to each coverage criterion by name, before the request goes out. Pull the exact NCD or LCD, read its criteria, and build the packet against them, criterion by criterion, in an evidence worksheet or whatever your practice already uses.

The same discipline applies wherever AI drafts text into the chart. A clean, fluent document isn't a supported one, which is why AI-generated notes still need coder QA before anyone relies on them.

WISeR does not touch Medicare Advantage risk adjustment

Read this twice if you code risk adjustment. CMS states plainly that WISeR "does not apply to people with Medicare Advantage and will have no impact on them." WISeR lives in Original Medicare fee-for-service.

So a WISeR non-affirmation isn't a RADV finding and doesn't touch a risk score. It's a coverage call on one procedure. If you work both sides of the house, keep the two files apart: the documentation standard that defends a diagnosis in a RADV audit is a different standard from the one that gets a nerve stimulator authorized, and CMS's quarterly RADV audit expansion is a separate track entirely.

Worth noting, because it explains where the model came from: CMS's own notice observes that some MA plans already work with third parties using AI, ML, or algorithmic decision logic in utilization management, under guardrails such as 42 CFR 422.566(d), which requires that an adverse medical-necessity decision on a prior authorization request be reviewed by a physician or other appropriate health care professional. WISeR imports that shape into fee-for-service.

What happens next in Congress

Senator Ron Wyden introduced S.J.Res.192 on May 19, 2026, a joint resolution of disapproval aimed squarely at the WISeR notice. It has 20 cosponsors and was placed on the Senate Legislative Calendar under General Orders, Calendar No. 431, on June 9, 2026.

It hasn't passed. A CRA joint resolution has to clear both chambers and be signed by the President before CMS would be required to unwind the model. Until that happens, every claim for a listed service in a listed state goes through the same review it went through last week.

So don't rework your documentation because a resolution is pending. Rework it because the coverage policy is already binding, on every listed claim in every listed state, resolution or not.