As soon as a topic engages your interest and you begin to research it, you should also be conducting a preemption check. Even as you gather research that will help you narrow your topic and create a thesis, you will be checking to see if your idea has been preempted by other writers or events.
The purpose of a preemption check is to determine if an author has covered your topic in a substantial article, or book, or if a court case or piece of legislation will resolve your topic. You do not want to devote time to a topic that has already been examined exhaustively or that will be rendered meaningless by a forthcoming court decision or enacted law. However, a topic that has been addressed by other authors still may be a valid choice if you can make a unique argument or change jurisdictions.
Preemption checks begin when you start your topic research and must be repeated regularly until publication. Follow these preemption check steps before you settle on your topic and thesis, while you are still researching a wider variety of sources for ideas. Repeat the process frequently until you submit your final draft.
Step 1: Search full-text law review databases.
Lexis and Westlaw have law journal coverage from about 1980-forward. Hein has the complete run of any law reviews in its database and is a good place to start a subject search. Your preliminary search for a topic would include full text articles in Law Reviews and Journals in Lexis, Law Reviews and Journals in Westlaw, and the Law Journal Library and smaller periodicals (e.g., Bar Journals) in HeinOnline. Use Scholar Check in Hein to help locate citing materials for particular articles or authors. While these databases overlap to some extent, you should still check each one because the contents and dates of coverage vary.
Step 2: Search legal periodicals indexes.
Your search also should include the Legal Resource Index on Westlaw, and LegalTrac, which is available on the Eckstein Library homepage. These two indexes include citations for additional articles not in the full-text law journal databases. When you search an index, you are not searching the full text of an article, so you will search by subject. If you locate an abstract on LegalTrac or in Legal Resource Index that appears relevant, you can look for the full text article on HeinOnline, Lexis or Westlaw. If you cannot find it there, ask a librarian for help. You might need to do an ILL, or it may be located in print at Eckstein.
Step 3: Consider whether you are researching an issue with interdisciplinary, non-legal dimensions. If you are, search full text databases from appropriate disciplines. Start with MarqcatPlus, which aggregates several (but not all) Raynor Library databases. Also conduct research in appropriate subject databases on the Raynor databases page. When you reach the Raynor home page, choose Articles & Databases, then use the drop-down menu to choose a topic or discipline. Once you click on a topic, a page will open showing individual databases at Raynor that may include relevant articles in the subject area you chose.
For example: Articles & Databases >> Chooses a Topic/Discipline >> Bioethics >> Bioethics Databases
If you know the name of a database you would like to search, for example, ABI Inform Global, you can locate it in the list of Databases A-Z on the Raynor Library page. Then you can search just that database. Ask for help if you are having difficulty or think you might be missing some relevant databases in your research.
Use indexes appropriate to the discipline, too. Indexes will be listed along with full text databases on Raynor’s A-Z list of databases.
Step 4: Search for books (and book chapters) covering your topic.
Use the catalog called WorldCat. It will allow you to search thousands of library catalogs simultaneously. WorldCat results include books, serials, mixed media, and can be sorted.
Step 5: Very important! Search working papers.
You must search both SSRN and bepress. Both repositories will allow you to see what authors are working on before the articles are formally published. SSRN has more disciplines than law, and there are millions of articles. Rather than limit the database to just law, you could search with very tailored search terms to elicit non-legal articles that might be similar to your topic. Try searching broadly and narrowly on SSRN. In the bepress legal repository, be sure to chose the "across all repositories" option so you are not just searching Marquette's repository.
Step 6: KeyCite and Shepardize any cases and statutes that are relevant to your topic.
For cases, check Shepard's and KeyCite to see if there is any subsequent history, including whether a petition for review has been filed. For statutes, check to see if there is proposed legislation that could substantially change the law.
Using two citators is a very good idea for preemption checks, as they operate slightly differently and something may turn up more obviously in one.
At any point in your topic selection, thesis development, and preemption research, you may find you have research questions. You may also have substantive legal questions along the way. If you encounter challenges, ask questions. Get advice from a librarian or a subject specialist as you go through the comment process.