Who are the various personnel who participate in the courtroom?How does each rol

Who are the various personnel who participate in the courtroom?How does each role affect and impact shaping procedural law(s)? Howdoes each role affect and impact shaping substantive law(s)? Whatchanges would you recommend to improve the role of the variouspersonnel who have a direct affect in shaping laws relating to thecriminal justice system?