The prosecutor in a criminal case shall:
(a) refrain from prosecuting a charge that the prosecutor knows is not supported by probable cause;
(b) make reasonable efforts to assure that the accused has been advised of the right to, and the procedure for obtaining, counsel and has been given reasonable opportunity to obtain counsel;
(c) not seek to obtain from an unrepresented accused a waiver of important pretrial rights, such as the right to a preliminary hearing;
(d) make timely disclosure to the defense of all evidence or information known to the prosecutor that tends to negate the guilt of the accused or mitigates the offense, and, in connection with sentencing, disclose to the defense and to the tribunal all unprivileged mitigating information known to the