Legal Questions

When does a court vacate, modify or confirm a no-fault arbitrator’s or master arbitrator’s award under CPLR article 75?

Short answer: Settled statewide by the Court of Appeals. The standard comes from the Court of Appeals: in compulsory no-fault arbitration the award must have evidentiary support and a rational basis and not be arbitrary and capricious (Petrofsky 1981; MVAIC v Aetna 1996), the master arbitrator may correct errors of law but courts review a master arbitrator's legal ruling only for irrationality (Smith 1982), an award beyond the policy limits exceeds the arbitrator's power and the point is not waived (Brijmohan 1998), and an arbitrator's legal error alone is not a ground (Falzone 2010, a SUM award, in the database). All four departments apply it; decisions differ only in applying it. The First Department vacates more readily where the award 'irrationally ignored' controlling First Department law presented to the arbitrator (Global Liberty v Professional Chiropractic 2016 and its IME no-show line, Therapeutic PT 2017) and has vacated an award as 'incorrect as a matter of law' (McMahon 2019, CPT Assistant), while the Second Department stresses that 'mere errors of law are insufficient' (Acuhealth 2019, Big Apple 2025) yet also vacates irrational legal rulings (Advanced Orthopaedics 2022). That is a difference of emphasis, not a conflicting rule; the attorney may prefer to show it.

Scope. Deciding this question means ruling, in a CPLR article 75 proceeding (petition, cross-petition or motion to vacate, modify or confirm) on an award made in a first-party no-fault arbitration under Insurance Law § 5106 (b) (AAA arbitrator) or by a no-fault master arbitrator under 11 NYCRR 65-4.10, on whether the award stands. Because this arbitration is compulsory, courts ask whether the award had evidentiary support, a rational basis and was not arbitrary and capricious (Petrofsky), and whether the arbitrator or master arbitrator exceeded a limit on their power (an issue not raised by the parties, an award beyond the policy limits, a master arbitrator re-weighing the evidence); a mere error of law, especially by a master arbitrator, is not enough (Smith; Falzone). The parties may be a provider-assignee, an injured person (lost wages, APIP) or the insurer, MVAIC or a self-insurer. The mandatory confirmation of an award when vacatur is denied (CPLR 7511 [e]) and the confirmation of an award revived when a § 5106 (c) de novo action is dismissed not on the merits are part of the topic but are not categories of their own (see relevance_guide).

Based on 178 decisions in our database, the most recent decided October 22, 2026.

Leading authorities · Governing regulations · Authority map · Decisions by court · Plain-text version (Markdown)

Leading authorities

  • Matter of Falzone (New York Cent. Mut. Fire Ins. Co.) (2010 NY Slip Op 07417) Court of Appeals, 2010Arbitral legal error alone is not a ground for vacaturA court may vacate an arbitration award only if it violates a strong public policy, is irrational, or clearly exceeds a specifically enumerated limitation on the arbitrator's power; a SUM arbitrator's refusal to give collateral-estoppel effect to an earlier no-fault award was a claim of legal error the courts cannot review, so the award was confirmed.
    It is well settled that a court may vacate an arbitration award only if it violates a strong public policy, is irrational, or clearly exceeds a specifically enumerated limitation on the arbitrator’s power
    Later history: Affirms Matter of Falzone, 64 AD3d 1149 (4th Dept 2009, 3-2; post 8404). The award reviewed was a SUM award; the no-fault decisions cite it for the general rule
  • Matter of Acuhealth Acupuncture, P.C. v Country-Wide Ins. Co. (2019 NY Slip Op 07246) Appellate Division, Second Department, 2019Compulsory-arbitration standard; master arbitrator's legal error not reviewableCourts reviewing a master arbitrator's award ask only whether it had evidentiary support, was rational or had a plausible basis; because the insurer submitted evidence of fraudulent incorporation, the master arbitrator's affirmance was not subject to vacatur even if it was an error of law, so the award was confirmed.
    A court reviewing the award of a master arbitrator is limited to the grounds set forth in CPLR article 75, which include, in this compulsory arbitration, the question of whether the determination had evidentiary support, was rational, or had a plausible basis
  • Matter of Global Liberty Ins. Co. v Professional Chiropractic Care, P.C. (2016 NY Slip Op 04156) Appellate Division, First Department, 2016First Department: award ignoring controlling law is arbitraryThe master arbitrator's award was arbitrary because it irrationally ignored First Department law, presented to the master arbitrator, that the assignor's failure to attend scheduled IMEs voided the policy ab initio; an alleged error in the denial form was no rational basis for the award, which was vacated.
    The master arbitrator’s award was arbitrary because it irrationally ignored the law, which petitioner insurer had presented to the master arbitrator, that the no-fault policy issued by petitioner was void ab initio due to respondent’s assignor’s failure to attend duly scheduled independent medical exams
    Later history: Reverses Supreme Court, Bronx County, 2015 NY Slip Op 50936(U) (post 5448)
  • Matter of Ameriprise Ins. Co. v Kensington Radiology Group, P.C. (2020 NY Slip Op 00500) Appellate Division, First Department, 2020Award beyond policy limits exceeds the arbitrator's powerBesides irrationality, an award may be vacated if the arbitrator exceeded his or her power, as by an award beyond the policy limits; the defense may be supported by evidence first offered in court, and the Appellate Term's remand for a framed-issue hearing on whether the policy was exhausted before the unverified claims became payable was affirmed.
    The defense that an award exceeds an arbitrator’s power is so important that a party may introduce evidence for the first time when the other party tries to confirm the award
    Later history: Affirms App Term, 1st Dept, 2017 NY Slip Op 51911(U) (post 3840)
  • Matter of 563 Grand Med., P.C. v Country-Wide Ins. Co. (2026 NY Slip Op 04292) Appellate Division, Second Department, 2026Arbitrator who raises an unpleaded issue sua sponte exceeds powerAn arbitrator's authority extends only to the issues the parties present; because the insurer never asserted lack of standing, the arbitrator impermissibly raised it sua sponte, and vacatur of the master arbitration award affirming that denial was proper.
    Here, Country-Wide failed to assert at the arbitration proceeding that Grand Medical lacked standing. Instead, the arbitrator impermissibly raised the issue of standing sua sponte
    Later history: Followed for the second master award in the same dispute, 2026 NY Slip Op 04290 (post 15724), decided the same day
  • Matter of Fishkin (Allstate Ins. Co.) (2019 NY Slip Op 08060) Appellate Division, Fourth Department, 2019Master arbitrator may not review the evidence de novoA master arbitrator who re-weighed the peer review evidence instead of deciding whether the arbitrator's medical-necessity award was incorrect as a matter of law exceeded his powers; vacatur of the master award and confirmation of the lower award were affirmed.
    Here, we agree with petitioner that the master arbitrator impermissibly performed a de novo review of the medical evidence, and thus clearly exceeded his powers.
  • Matter of Petrofsky (Allstate Ins. Co.) 54 NY2d 207Compulsory no-fault arbitration: award must have evidentiary support and a rational basis and not be arbitrary and capricious; defines the master arbitrator's review role. Cited by 88 decisions in the database.Not in our database.
  • Matter of Smith (Firemen's Ins. Co.) 55 NY2d 224Master arbitrator may vacate for error of law; courts will not vacate for an incorrect application of substantive law unless so irrational as to require vacatur. Cited by 41.Not in our database.
  • Matter of Motor Veh. Acc. Indem. Corp. v Aetna Cas. & Sur. Co. 89 NY2d 214Compulsory arbitration award upheld if supported by evidence and not arbitrary or capricious, even if legally erroneous. Cited by 85 (many in MVAIC/priority contexts).Not in our database.
  • Matter of Brijmohan v State Farm Ins. Co. 92 NY2d 821Award beyond the policy limits exceeds the arbitrator's power; the objection is not waived when raised in opposition to confirmation. Cited by 9.Not in our database.
  • Matter of Liberty Mut. Ins. Co. v Spine Americare Med. 294 AD2d 574Master arbitrator's factual review limited to rationality; legal ruling upheld unless irrational; 'mere errors of law are insufficient'. Cited by 24.Not in our database.
  • Matter of Allstate Ins. Co. v Keegan 201 AD2d 724Master arbitrator has no power to review the matter de novo. Cited by 16.Not in our database.
  • Acuhealth Acupuncture, P.C. v Country-Wide Ins. Co. 170 AD3d 1168'The master arbitrator's determination of the law need not be correct'; also attorney's fees under 65-4.10 (j) (4). Cited by 28; not in the database.Not in our database.
  • Matter of Exclusive Med. & Diagnostic v Government Empls. Ins. Co. 306 AD2d 476Upon denying a petition to vacate, the court must confirm the award (CPLR 7511 [e]); the standard App Term 2d citation. Cited by 27.Not in our database.
  • Matter of Shand (Aetna Ins. Co.) 74 AD2d 442Rational-basis review of compulsory no-fault awards. Cited by 36.Not in our database.
  • Countrywide Ins. Co. v Sawh 272 AD2d 245Arbitrators exceeded their authority by awarding beyond the $50,000 policy limit. Cited by 11.Not in our database.
  • Country-Wide Ins. Co. v Zablozki 257 AD2d 506First Department standard: award supported by evidence or other basis in reason. Cited by 14.Not in our database.
  • Matter of Joan Hansen & Co., Inc. v Everlast World's Boxing Headquarters Corp. 13 NY3d 168An arbitrator's authority extends only to the issues the parties present; relied on in 563 Grand Med. (2026) for the sua sponte ground.Not in our database.

Governing regulations

The court's standard (evidentiary support and a rational basis, not arbitrary and capricious, no excess of power; a mere error of law is not enough) comes from CPLR 7511 and the case law; on denying vacatur the court must confirm the award (CPLR 7511 (e)).

  • 11 NYCRR 65-4.10 (h) A master arbitrator's award is final and binding except for a CPLR article 75 proceeding or, when the award is $5,000 or more (excluding interest and attorney's fees), a de novo action.
  • 11 NYCRR 65-4.10 (a) An arbitrator's award may be vacated or modified solely by appeal to a master arbitrator: on the article 75 grounds, or because the award exceeds the policy limits (a) (2), is incorrect as a matter of law (a) (4) or awards a fee outside 65-4.6.

Also relevant

Chosen by us from the regulation text and the decisions on this question that cite it. Each link opens our copy of the regulation, which is unofficial; the official text is in the NYCRR.

Authority map

Each circle is a decision on this question, placed by court and date; its colour is the position it took. Lines are citations between them. Select a circle (or find a decision by name) to see its links and summary. The same decisions are listed by court below the map.

No ground for vacatur or modification shown: the award is confirmed or left in placeAward vacated or modified because it was irrational, arbitrary and capricious, without evidentiary support or contrary to settled lawAward vacated because the arbitrator exceeded a limit on his or her power (issue not raised, beyond policy limits, public policy) or on another CPLR 7511 (b) groundMaster arbitrator's award vacated because the master arbitrator went beyond the limited review allowed by 11 NYCRR 65-4.10The court cannot decide on the record whether a ground for vacatur exists and orders a hearing or a determination belowRing: rules on the question, but another ground decided the caseContrasted, distinguished or limitedDeclined to follow, questioned, overruled or reversedCited
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How the rule was applied, by court

Decisions (178)

Every decision in our database that rules on this question: highest court first, then by department, newest first. 166 turn on it; the others rule on it alongside a different main ground (marked "also decides"). The one-sentence summaries describe what each court said on this question.

How this page is made: the decisions are those in our case-law database that cite this question's leading cases or were tagged with its subject. A language model read each one in full and recorded whether it rules on the question, the position it took and a one-sentence summary; a second, independent reading checked every entry. Court, department, date and the citation links come from the database. Read the decision before relying on it.