Judges vary widely in how they approach interviews. Some conduct simple, lightweight "getting-to-know-you" sessions. At the other extreme, some reportedly ask applicants pointed, substantive questions such as "What did you learn in your Torts class?" or "What do you think of this Court's opinion in Doe v. Smith ?" Before going to an interview, find out as much as you can about the particular judge's approach so you can prepare accordingly. If possible, speak with one of the judge's former clerks or with students who interviewed with the judge (whether or not they received an offer). Ask them what they think the judge is looking for in a clerk and what types of questions to expect. Also consider speaking with a professor or employer who may know the judge personally or professionally.
Review any biographical information you can find about the judge. Good sources are the Almanac of the Federal Judiciary, the news databases in Lexis and Westlaw, and an Internet search engine such as "Google." In addition, read a few of the judge's opinions, including dissents and concurrences. Opinions reveal a great deal about the judge's philosophy and writing style. A good place to start is the "Noteworthy Rulings" section of the Almanac of the Federal Judiciary or a caselaw search on Lexis or Westlaw. Do not get carried away in reading a judge's opinions, however, to the detriment of other methods of preparation, class work, and/or sleep!
Review your résumé and be prepared to talk about anything on it and to highlight your qualifications – particularly research, writing, and analytical experience. Also review your writing sample in detail and be prepared to discuss it in depth.
Finally, you should review the sample interview questions and think about your responses. While these questions do not represent the universe of potential questions, they are some of those most commonly asked. In addition, judges undoubtedly will give you an opportunity to ask questions yourself, so you must have some prepared in advance.