Adversary System

Adversary System in the United States

A set of processes intended to allow opposing parties in a dispute to present their arguments. Under the adversary system, formal notice is served on the party against whom an action has been filed to allow that party an opportunity to respond. The adversary system is typically self-initiated although the prosecuting attorney acts on behalf of the victim and the public in criminal matters. The burden of proof falls to the parties under the adversary system. Most often, the judge’s role is to preside over the proceeding rather than function as an actual fact-finder. The outcome in an adversary proceeding is almost always all or nothing, and, unlike mediation or conciliation, is zero-sum in character. That means there is seldom a middle-ground outcome, and whatever the successful party wins is necessarily lost by the unsuccessful party. The outcome of such proceedings is authoritative; it is enforced upon the losing party. An adversary proceeding is different from an ex parte proceeding, where only one party appears. An adversary proceeding also differs from a summary proceeding, where no significant fact dispute exists and where the court may hasten and simplify the resolution of an issue.

See Also

Advisory Opinion (Judicial Function) Controversy (Judicial Function).

Analysis and Relevance

The assumption underlying the adversary system is that out of the legal and factual contest of the parties the truth will emerge. The adversary system forces a plaintiff and defendant in a legal action to contest each other with evidence gathered in support of their respective cases. The system is generally regarded as the most effective means of evaluating evidence. The adversary system also features a diffusion of power among its principal participants, such as judge, prosecutor, jury, and defense counsel. Each actor helps to produce a check and balance effect, thus safeguarding against arbitrary or abusive judgments.

Notes and References

  1. Definition of Adversary System from the American Law Dictionary, 1991, California


See Also

  • Legal Topics.
  • Criminal Justice System; Criminal Procedure: Comparative Aspects; International Criminal Courts; International Criminal Justice Standards; Prosecution: Comparative Aspects; Trial, Criminal.

    Alternative Dispute Resolution; Civil Law; Common Law; Inquisitorial System; Judge; Judiciary; Jury.

    Faretta v. California, 422 U.S. 806 (1975).

    Malloy v. Hogan, 378 U.S. 1, 7 (1964).

    Miranda v. Arizona, 384 U.S. 436, 460 (1966).

    Further Reading (Books)

    Dama_ka, Mirjan. “Evidentiary Barriers to Conviction and Two Models of Criminal Procedure: A Comparative Study” University of Pennsylvania Law Review 121 (1973): 507_589.

    Evidence Law Adrift. New Haven: Yale University Press, 1997.

    Esmein, AdhÉmar. A History of Continental Criminal Procedure, with Special Reference to France. Translated by John Simpson. Boston: Little, Brown, 1913.

    Frase, Richard S. “Comparative Criminal Justice Policy, in Theory and in Practice.” In Comparative Criminal Justice Systems: From Diversity to Rapprochement. Vol. 17 in Nouvelles Études Pénales. Toulouse, France: Eres, 1998. Pages 109_121.

    Fuller, Lon L. The Adversary System: Talks on American Law. Edited by Harold J. Berman. New York: Vintage Books, 1961.

    Goodpaster, Gary. “On the Theory of American Adversary Criminal Trial.” Journal of Criminal Law & Criminology 78 (1987): 118_152.

    Goldstein, Abraham. “Reflections on Two Models: Inquisitorial Themes in American Criminal Procedure.” Stanford Law Review 26 (1974): 1009_1025.

    Hermann, Joachim. “Various Models of Criminal Proceedings.” South African Journal of Criminal Law and Criminology 2, no. 1 (1978): 3_19.

    Landsman, Stephen. Readings on Adversarial Justice: The American Approach to Adjudication. St. Paul, Minn.: West Publishing Co., 1988.

    Langbein, John H. “The Criminal Trial before the Lawyers.” University of Chicago Law Review 45 (1978): 263_316.

    -, and Weinreb, Lloyd L. “Continental Criminal Procedure: Myth and Reality.” Yale Law Journal 87 (1978): 1549_1568.

    Ploscowe, Morris. “The Development of Present-day Criminal Procedures in Europe and America.” Harvard Law Review 48 (1935): 433_473.

    Pound, Roscoe. “The Causes of Popular Dissatisfaction with the Administration of Justice.” In Report of the Twenty-ninth Annual Meeting of the American Bar Association. Philadelphia: Dando, 1906. Pages 395_408.

    Schlesinger, Rudolf. “Comparative Criminal Procedure: A Plea for Utilizing Foreign Experience.” Buffalo Law Review 26 (1976): 361_385.

    Further Reading (Books 2)

    Sheppard, Blair H., and Vidmar, Neil. “Adversary Pretrial Procedures and Testimonial Evidence: Effects of Lawyer’s Role and Machiavellianism.” Journal of Personality and Social Psychology 39 (1980): 320_332.

    Thibaut, John W., and Walker, Laurens. Procedural Justice: A Psychological Analysis. Hillsdale, N. J.: Laurence Erlbaum Associates, 1975.

    “A Theory of Procedure.” California Law Review 66 (1978): 541_566.

    Van Kessel, Gordon. “Adversary Excesses in American Criminal Trials.” Notre Dame Law Review 67 (1992): 403_549.

    Weinreb, Lloyd L. Denial of Justice. New York: Macmillan, 1977.

    Further Reading (Articles)

    Reasoning system thinks one step ahead of adversary, Signal; June 1, 2001; Sheehy, Christian B

    US Patent Issued to L-3 Communications on May 8 for “Radio Communications System and Method Having Decreased Capability for Detection by an Adversary” (Utah Inventors), US Fed News Service, Including US State News; May 15, 2012

    Sharpening the spear through innovative acquisition: the F-5 Adversary Program.(PROGRAM MANAGEMENT), Defense AT & L; May 1, 2009; Bolles, Jay Broadus, William Conroy, William F. Goff, Jason Ingalls, Mike Kotzian, Mike Mallicoat, Duane Wallace, James

    Most states’ utility panels have an adversary system., The Atlanta Journal-Constitution; February 15, 2006

    The Resilience of the Adversary Culture, The National Interest; June 22, 2002; Hollander, Paul

    A Modern Legal Ethics: Adversary Advocacy in a Democratic Age.(Book review), Michigan Law Review; April 1, 2010; Freedman, Monroe H. Smith, Abbe

    Ethics for Adversaries: The Morality of Roles in Public and Professional Life.(Review), American Political Science Review; June 1, 2000; Sabia, Dan

    Victims’ Rights in an Adversary System, Duke Law Journal; November 1, 2008; Blondel, Erin C.

    Eliminating Adversary WMD: Lessons for Future Conflicts, Strategic Forum; October 1, 2004; Hersman, Rebecca K. C. Koca, Todd M.

    Synthetic Adversaries for Urban Combat Training, AI Magazine; September 22, 2005; Wray, Robert E. Laird, John E. Nuxoll, Andrew Stokes, Devvan Kerfoot, Alex


    Intelligent Adversary Modeling of Homeland Security Networks, IIE Annual Conference. Proceedings; January 1, 2013; Parnell, Gregory S. Burk, Roger C. Merrick, Jason

    Allies, Adversaries, and International Trade., American Political Science Review; September 1, 1995; Ward, Michael D.

    US Patent Issued to Microsoft on March 18 for “Detection of Adversaries through Collection and Correlation of Assessments” (American, Israeli Inventors), US Fed News Service, Including US State News; March 18, 2014


    How Two Bitter Adversaries Hatched A Plan To Change The Egg Business, NPR Morning Edition; February 10, 2012; Dan Charles

    VMFT-401: Adversary tactics experts, Naval Aviation News; January 1, 2002; Llinares, Rick


    “Methods and Apparatus for Simulating Risk Tolerance and Associated Adversary Costs in a Distributed Business Process” in Patent Application Approval Process, Politics & Government Week; July 4, 2013

    Do OPSEC and risk management mesh? OPSEC and risk management both use an analytical process to prevent adversaries from exploiting assets. But there are key differences. (Viewpoint).(Department of Defense’s operational security program model), Security Management; November 1, 2001; Pattakos, Arion N.

    Adversary System: Open and Free Legal Research of US Law

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