Judicial systems have been used primarily throughout the world to resolve disputes in varied contexts, where criminal defendants, law enforcement officers, and expert witnesses participate daily in resolving deputies in a judicial manner (Silverman et al 2010). However, the characteristics of judicial systems differ from country/region to country, depending on the basis of the system which may impact the expert witness. To explain the above statement, one could say that legal systems fall into two systems, the adversarial system and the inquisitorial system. Conversely, a hybrid between these two systems formed another system called the mixed system. These arise from historical law and judicial practices practiced for considerable time, which have eventually improved and become standardized. Debara.K suggested in 2002 that the basis for forming a jury was based on medieval track fighting modes where two sides argued their points to crown a champion. Jonakait (2008) concluded that in the 18th century, legal systems evolved to a stage where lawyers actively participated in English criminal trials, making the legal system more "adversarial". Paradoxically, the inquisitorial system was born just after the 13th century, following a disbelief in the accusatory system. Essentially, this system was formed by the French and then transferred horizontally to a few additional countries which eventually became one of the two dominant legal systems in the world (Johnson. Het al 2008). In this short study, the English legal system will be elaborated. in relation to the Italian legal system. Before that, the adversarial and inquisitorial systems will be discussed... middle of article...... and Jones, M. (2008) History of criminal justice, 4th ed. Waltham: Elsevier, p.67-70. Jonakait, R. (2008) The rise of the American adversarial system: America before England, Widner Law review, 14(1), p.656. Koppen, J. and Penrod, S . (2003) Adversarial versus inquisitorial justice: a psychological perspective on criminal justice systems, United States: Springer, p.29. Malleson, K. (2007) the legal system, New York: Oxford University press, p.11-14. Siegal, L. (2010) Criminology: The core, United States: Cengage learning, p.385-387. Silverman , J. and Silverman, S. (2010) how the judicial system works, United Kingdom: A Discovery company, p.27. Smith , S. and Langan, B. (1992) Civil jury cases and verdicts in large countries, Burean of Justice Statistics, - (1), p.3-10.Wall, W. (2010) Forensic Science in courts: the role of the expert witness, West Sussex: John Wiley and Sons, p.2-56.