John S. Diaconis


Mr. Diaconis is a member of our Insurance and Employment Practice Groups. His more than 33 years of experience includes tenure as Vice President of Hartford Financial Services Group.

Mr. Diaconis counsels clients in the insurance and reinsurance industry and acts as defense and coverage counsel, mediator and arbitrator in the investigation and resolution of fidelity, commercial crime and financial institution bond claims, insurance company errors and omissions, employment, insurance agents and brokers, specified medical professions and medical benefits claims, and directors' and officers' claims. He also serves as an arbitrator and mediator in insurance and reinsurance arbitrations and mediations.

Mr. Diaconis received his formal mediation training at Harvard Law School, Program of Instruction for Lawyers and at the Westchester Mediation Center, in conjunction with New York State Office of Court Administration. He is appointed to the Roster of Neutrals for New York Supreme Court, Commercial Divisions, for both New York and Westchester Counties.

Reported Cases 

  • Woods v. Enlarged City School District of Newburgh, 473 F.Supp.2d 498 (S.D.N.Y. 2007) (summary judgment granted on Title VII race discrimination claim).
  • Manbeck v. Katonah-Lewisboro School District, 435 F.Supp.2d 273 (S.D.N.Y. 2006) (age restriction under New York State Law for entrance to public school upheld on motion to dismiss).
  • Manbeck v. Katonah-Lewisboro School District, 403 F.Supp.2d 281 (S.D.N.Y. 2005) (injury from claimed unconstitutional age requirement in Education Law not irreparable).
  • Brennan v. City of White Plains, 1998 WL 75692 (S.D.N.Y.) (municipality's actions directed to only one individual may constitute policy of discrimination under Title VII).
  • Albert T. Chandler v. H.E. Yerkes and Associates, Inc., 1994 WL 538906 (S.D.N.Y.) (failure to produce documents does not warrant dismissal under Rule 37(b)2 and 41(b)).
  • Albert T. Chandler v. H.E. Yerkes and Associates, Inc., 784 F.Supp. 119 (S.D.N.Y. 1992) (material issue whether procurement of insurance for Thai Buddha and fable god statues valued at $30 million was impossible in light of cancellation by prior insurer).
  • W.A. Knight v. H.E. Yerkes and Associates, Inc., 135 F.R.D. 67 (S.D.N.Y. 1991) (dismissal for failure to prosecute not warranted under Rule 41 (b)).
  • Travelers Insurance v. Buffalo Reinsurance Company, 1990 WL 116741 (S.D.N.Y.) (amended pleading allowed to assert breach of warranty of retention through use of retrospective premium plan).
  • Travelers Insurance v. Buffalo Reinsurance Company, 739 F.Supp. 209 (S.D.N.Y. 1990) (material issue whether cedent's two and one-half month delay in providing notice vitiated reinsurance coverage).
  • Katz Broadcasting of Atlanta v. Alexander and Alexander of New York, 1990 WL 67433 (S.D.N.Y.) (loss to antenna and transmission-related equipment at tower cite not a “covered location”).
  • American Marine Insurance Group v. Price Forbes, et al., 560 N.Y.S.2d 638 (1st Dept. 1990) (U.S. legal proceedings should not proceed where related action was pending inUnited Kingdom).
  • Hvide Marine International, Inc. v. Employers of Wassau, 1989 WL 140280 (S.D.N.Y.), (addressing claims against Lloyd’s under sue and labor clause of marine policy).
  • Corcoran v. AIG Multi-Line Syndicate, et al., 143 Misc. 2d 62, 539 N.Y.S.2d 630 (Sup. Ct. N.Y. 1989), rev'd, 562 N.Y.S.2d 933 (1stDept. 1990) (liquidation of insurer abrogated arbitration clause in reinsurance contract).
  • Wartski v. M.F.Y. Legal Services, Inc., N.Y.L.J. 6/26/85 at 11,Col. 7 (Sup. Ct. N.Y. 6/25/86).
  • Port Chester Yacht Club, Inc. v. Iasillo, et al., 614 F.Supp. 318 (S.D.N.Y. 1985) (approval of redevelopment plan by Village not discrimination under 14th Amendment).
  • Compusort, Inc. v. Goldberg, CCH pp. 99, 211 (S.D.N.Y. 1983).
  • Copeland v. Salomon, 56 N.Y.2d 783 426 N.E.2d 1284 (1982) (failure to obtain permission from Court appointing receiver in mortgage foreclosure action no jurisdictional bar to suit). 
  • Koster v. Fenton, 84 A.D.2d 7783, 444 N.Y.S.2d 30 (2dDep't 1981) (reapportionment of liability among parties).


  • New York University School of Law, LL.M., 1988
  • Drake University Law School, J.D., 1980
    • Law Review, 1978-1980
  • State University of New York at Oneonta, B.A., 1976

Bar Admissions

  • New York
  • U.S. District Courts for the Eastern and Southern Districts of New York
  • U.S. Court of Appeals for the Second Circuit


  • American Bar Association
  • Westchester County Bar Associations
  • Co-Chair, Municipal Law Section of the Westchester County Bar Association
  • Chairperson, Practising Law Institute, Program on Reinsurance Law and Practice, 1994-2000

Professional Recognition and Community Involvement

  • Town of New Castle, Town Prosecutor, 2006-2009
  • Town of New Castle, Councilman, 2001-2005
  • Law Clerk for the Hon. Joel J. Tyler, U.S.M.J., U.S. District Court, Southern District of New York, 1980-1981