The degree was first awarded in the United States in the early 20th century and was created as a modern version of the old European doctor of law degree (such as the Dottore in Giurisprudenza in Italy and the Juris Utriusque Doctor in Germany and central Europe). Originating from the 19th century Harvard movement for the scientific study of law, it is a degree that in most common law jurisdictions is the primary professional preparation for lawyers. It involves a three-year program in most jurisdictions.
To be authorized to practice law in the courts of a given state in the United States, the majority of individuals holding a J.D. degree must pass a bar examination. The state of Wisconsin, however, permits the graduates of its two law schools to practice law in that state, and in its state courts, without having to take its bar exam—a practice called "diploma privilege"—provided they complete the courses needed to satisfy the diploma privilege requirements. In the United States, passing an additional bar exam is not required of lawyers authorized to practice in at least one state to practice in the national courts of the United States, courts commonly known as "federal courts". Lawyers must, however, be admitted to the bar of the federal court before they are authorized to practice in that court. Admission to the bar of a federal district court includes admission to the bar of the related bankruptcy court.
In the United States, the professional doctorate in law may be conferred in Latin or in English as Juris Doctor (sometimes shown on Latin diplomas in the accusative form Juris Doctorem) and at some law schools Doctor of Law (J.D. or JD), or Doctor of Jurisprudence (also abbreviated JD or J.D.). "Juris Doctor" literally means "Teacher of Law", while the Latin for "Doctor of Jurisprudence"—Jurisprudentiae Doctor—literally means "Teacher of Legal Knowledge".
The J.D. is not to be confused with Doctor of Laws or Legum Doctor (LLD or LL.D.). In institutions where the latter can be earned, e.g. Cambridge University (where it is titled Doctor of Law, though still retaining the abbreviation LLD) and many other British institutions, it is a higher research doctorate representing a substantial contribution to the field over many years, beyond that required for a PhD and well beyond a taught degree such as the J.D. The LL.D. is invariably an honorary degree in the United States.