This report provides a comprehensive overview of the Law & Legal Systems in the United Kingdom. It begins with an introduction to the criminal justice system, highlighting the roles of various stakeholders and the importance of the rule of law. The main body delves into the different types of law, including common law, public law, and private law, with specific examples such as employment law and criminal law. The report also details the structure of the English court system, from the Magistrates' Court to the Supreme Court, and explains the appeals process. Key principles of criminal justice, such as Actus Reus and Mens Rea, are discussed, along with the involvement of agencies like the Crown Prosecution Service and the National Probation Service. The report concludes by summarizing the key aspects of the criminal justice system and its operation, including the challenges and measures of effectiveness. This report offers a detailed analysis of the UK's legal framework, making it a valuable resource for students studying law and related fields.