or by other federal rules, privileges in the federal courts would be "governed by the principles of the common law as they may be interpreted by the courts of the United States in the light of reason and experience". Rule 501 meant that the entire purpose of the FRE (to provide clarity and supersede prior case law) was defeated in the specific context of the law of privileges. Thus, to this day, attorneys practicing in U.S. federal courts must carefully research current case law to determine the contours of available privileges in the particular circuit and district in which their case is being heard. In contrast, the California Evidence Code, from which the original proposal had been drawn, had expressly codified all evidentiary privileges and then displaced the common law, so that any further privileges in the courts of that state would have to come from the California State Legislature. Impeachment by Conviction – Rule 609(a): The rule specified when a party could use evidence of a prior conviction to impeach a witness. Congress reformed most of Rule 609(a), to specify when a court could exercise discretion to admit evidence of a conviction which was a felony, but that the court must admit the prior conviction if the crime was one involving "dishonesty or false statement". The Advisory Committee Notes still function as an important source of material used by courts to interpret the Rules. Even though the Federal Rules of Evidence are statutory, the Supreme Court is empowered to amend the Rules, subject to congressional disapproval. However, amendments creating, abolishing, or modifying privileges require affirmative approval by Congress under . Purpose In general, the purpose of rules of evidence is to regulate the evidence that the jury may use to reach a verdict. Historically, the rules of evidence reflected a marked distrust of jurors. The Federal Rules of Evidence strive to eliminate this distrust, and encourage admitting evidence in close cases. Even so, there are some rules that perpetuate the historical mistrust of jurors, expressly limiting the kind of evidence they may receive or the purpose for which they may consider it. At the same time, the Rules center on a few basic ideasrelevance, unfair surprise, efficiency, reliability, and overall fairness of the adversary process. The Rules grant trial judges broad discretion to admit evidence in the face of competing arguments from the parties. This ensures that the jury