Your article must be original to be publishable in a law journal. If other articles have already been published on your topic and they cover the topic so thoroughly that there is nothing new for you to add to the conversation, then your article is not original and it has been preempted.
A preemption check is essentially a thorough search of the legal literature to find every article that has already been written on your topic to determine whether someone has already published the same article as the one that you are planning on writing.
In addition to being necessary to publish (your article must be original in order to be publishable), a preemption check will also:
Save you time: A thorough preemption check will save you from researching and writing about a moot topic, or from having to come up with a new topic far into the semester (this frequently happens to students who don't do a preemption check early on in the research and writing process!).
Jumpstart your research: Finding published articles on your topic and seeing how others have analyzed the issue is not only necessary for a preemption check, but it also serves as the initial research for your own article.
Improve your writing: Reading lots of law journal articles is the best way to get a sense of how to write a law journal article. By reading lots of articles during the preemption check process, you will have a better idea of how to organize and write your own article.
Improve your analysis: A good law journal article engages with other thoughtful scholars who have already published on topics related to what you are writing about. The quality of your article will be much better if you have a good understanding of the existing literature and you engage with that literature in your article.
You should do a preemption check:
Because it typically takes a long time to research, write, and publish a law journal article, it is important to repeat the preemption check process when submitting drafts and before publication to ensure your article is still original.
There are four basic steps for completing a preemption check:
Step 1: Search Google Scholar for articles on or closely related to your topic.
Step 2: Search the law journal databases on Westlaw and Lexis. It is important to search both, because Westlaw and Lexis do not have identical coverage for law review articles—some journals are available on Lexis but not Westlaw, and vice versa.
Step 3: Search the (less frequently used but highly useful) Index to Legal Periodicals database. If you have questions about accessing or searching in this database, please don't hesitate to ask a law librarian for help.
Step 4: Search the Social Science Research Network (SSRN) for forthcoming and recently published articles on your topic.
If you need help generating good search terms for your preemption check searches, see this guide from the U Chicago Law Library: Preemption Check Checklist: Generating Search Terms.
First of all, don't panic!
You may come across articles that are similar or related to your topic, but that does not necessarily mean that you cannot write about the topic too. You will have to exercise some judgment in deciding whether your topic has been preempted.
Key questions to ask yourself include:
Don't be too quick to reject a topic as preempted—there may be a way to adjust your claim or analysis or conclusion to avoid preemption—but also be willing to drop it if there really is nothing left for you to contribute.
If you aren't sure whether to proceed with a proposed topic, talk to your journal editors or faculty advisors.
Keep track of the relevant resources that you find throughout the topic selection and preemption check process by saving pdf copies and keeping track of citation information and links in one place (such as a Word doc, Google doc, OneNote, PowerNotes—whatever system works best for you).
Create permalinks as you go for resources that you find on the internet. You do not want to find months into your research and writing process that a key resource has disappeared from the open web! Here is a quick tutorial on how to create permalinks with Perma.cc: Perma Tutorial. Note that you do not need permalinks for articles that you find in a database like Westlaw or Lexis.
Don't procrastinate and don't hesitate to ask for help if you are feeling overwhelmed or stuck.
