Congress has not only established the exclusive rights of copyright but also has created exceptions and limitations to those rights. These limitations exist to encourage activities that Congress determines to be desirable and would be made difficult under copyright law. Many of these limitations are very specific in their focus, but fair use is much broader in when it can be applied.
This Crash Course video has an overview of why limitations to copyright exist under U.S. law and some of the more common limitations, including fair use.
Fair use: "a legal doctrine that promotes freedom of expression by permitting the unlicensed use of copyright-protected works in certain circumstances (U.S. Copyright Office)"
As the above quote from the Supreme Court states, fair use exists to allow for copyrighted materials to be used without a license in certain cases that would normally violate the exclusive rights of copyright. In these cases, the promotion of creative work that is the justification of the Copyright Clause of the Constitution is better served by not granting monopoly over the original work.
Congress wrote into Section 107 of the Copyright Act some examples reasons that unlicensed use of copyrighted work might be fair use: "criticism, comment, news reporting, teaching..., scholarship, or research (17 U.S. Code § 107)."
Let's use a thought experiment based on one of those examples to explain the logic of fair use. You are a journalist, and you discover a document from a major corporation admitting that they are violating environmental safety laws. You want to share material from that document to report on that violation, but that document is copyrighted material owned by the corporation. The corporation is not going to give you a license to use that material, but fair use can give you the ability to copy from the document without a license.
Section 107 sets out 4 factors that are considered when determining when an unlicensed use of copyrighted material is a fair use:
When trying to determine if your use of copyrighted material is fair, you have to balance the four factors against each other. While one factor may favor fair use, it could be outweighed by other factors (Crews Ch. 11 [UofM login required]).
You might be getting a sense from the sections above that whether something is fair use is not always clear cut. This is a strength and a weakness. The broad nature of fair use allows it to be adapted to new situations and contexts much more easily than other copyright limitations, but the vagueness can make people who want to use it feel less secure in their decisions.
These resources are designed to help you feel more secure using fair use. While they are not legal advice, they can help you think through whether what you want to do would be a fair use.
This document takes you through the four factors and is designed with educational uses in mind. Use it to help you think through your fair use case.
The Copyright Office's Fair Use Index is a search tool that tracks court decisions on fair use cases to help identify existing law. It allows you to narrow searches by legal jurisdictions and the types of works involved. It will summarize the case, but you will need to find full text of the case law elsewhere.
Best practice documents can give you a sense on fair use has been and should be applied. These best practice documents are produced by the American University School of Communication's Center for Media and Social Impact (formerly Center for Social Media) and Washington College of Law's Program on Information Justice and Intellectual Property.
Crews., Kenneth D. Copyright Law for Librarians and Educators : Creative Strategies and Practical Solutions. Fourth edition, ALA Editions, 2020. EBSCOhost, search.ebscohost.com/login.aspx?direct=true&db=nlebk&AN=2434646&site=eds-live&scope=site.
Stim, Richard. "Measuring Fair Use: The Four Factors." Stanford Copyright & Fair Use, Stanford Libraries, fairuse.stanford.edu/overview/fair-use/four-factors.
United States Code. Legal Information Institute, Cornell Law School, www.law.cornell.edu/uscode/text.
United States Copyright Office. "More Information on Fair Use." Copyright.gov, www.copyright.gov/fair-use/more-info.html.
United States Supreme Court. Iowa State University Research Foundation, Inc. v. American Broadcasting Companies, Inc. 12 May 1980. H20, Harvard Law School, h2o.law.harvard.edu/cases/5148.