Question: How does one become a law school teacher?
Answer: Professors in law schools are themselves lawyers and most often graduates of the best law schools in the country. These people also tended to distinguish themselves academically while in law school and may have been on their school's law reviews. some have practiced law before beginning to teach while others went directly into academic life. some law professors have also obtained advanced law degrees (called an LL.M) before teaching.
Additional information on this topic is available from the Association of American Law Schools.
Thanks to Lee Arbetman from Street Law, Inc for help in answering this question. Visit the Street Law web site!