Core New York Authorities

• Vehicle and Traffic Law § 311 — compulsory liability insurance definitions and minimum-limit framework.
• Insurance Law §§ 5102 and 5104 — no-fault basic economic loss, serious-injury threshold and noneconomic-loss rules.
• Insurance Law § 3420(f) — mandatory UM and supplementary uninsured/underinsured motorist coverage.
• CPLR § 1411 — comparative-negligence rules, including subsection (b) for Article 51 personal-injury actions commenced on or after May 26, 2026.
• DFS Circular Letter No. 3 (2026) — official guidance summarizing the 2026 motor-vehicle insurance reforms.

2026 Article 51 Changes

Part EE of Chapter 58 of the Laws of 2026 deleted the 90/180-day serious-injury category, changed procedural sequencing for fault and serious injury, added a limited $100,000 noneconomic-damages cap for specified at-fault claimants, and added CPLR § 1411(b). These provisions took effect May 26, 2026 for actions and proceedings commenced on or after that date.

Leading New York Decisions

• Pommells v. Perez, 4 N.Y.3d 566 (2005) — serious-injury proof, causation and gaps in treatment; use with the amended statutory definition.
• Matter of Metropolitan Property & Casualty Insurance Co. v. Mancuso, 93 N.Y.2d 487 (1999) — SUM exhaustion requirements.
• Raffellini v. State Farm Mutual Automobile Insurance Co. (N.Y. 2007) — serious-injury requirement in SUM claims.

Because the 2026 reforms are keyed to commencement date, research should identify whether an action or proceeding was commenced before or on/after May 26, 2026 and then separately analyze no-fault, serious-injury and SUM requirements.

Current-law review: September 17, 2026. Confirm subsequent history, effective-date rules, statutory amendments and current policy language before reliance.