The Supreme Court has ordered the state’s largest health insurance company to turn over consultant reports and other materials it relied on when establishing its two-tier OMNIA system to hospitals relegated to the second tier. The justices overturned a decision by the Appellate Division that denied the discovery request, rejecting the panel’s conclusion that the broad discovery request was not warranted because the challenge to the OMNIA system lacked merit.

The justices ordered disclosure of a McKinsey & Co. report commissioned by Horizon Healthcare Services when it decided which hospitals would be designated Alliance partners, its term for those in the first tier of the OMNIA system. The order also encompasses documents relating to the formulation of Tier 1 criteria, performance scores for all Tier 1 hospitals and communication between Horizon and Tier 1 partners. The OMNIA plan, which offers lower premiums and deductibles to patients who use the seven large hospital systems in Tier 1, is under challenge by hospitals in the second tier.