U.S. copyright law provides copyright owners with the following exclusive rights:
- Reproduce the work in copies or phonorecords.
- Prepare derivative works based upon the work.
- Distribute copies or phonorecords of the work to the public by sale or other transfer of ownership or by rental, lease, or lending.
- Perform the work publicly if it is a literary, musical, dramatic, or choreographic work; a pantomime; or a motion picture or other audiovisual work.
- Display the work publicly if it is a literary, musical, dramatic, or choreographic work; a pantomime; or a pictorial, graphic, or sculptural work.
-Perform the work publicly by means of a digital audio transmission if the work is a sound recording.
Copyright also provides the owner of copyright the right to authorize others to exercise these exclusive rights, subject to certain statutory limitations.
Combined, TurnItIn is offering a service that individual copyright holders are likely uninterested in providing themselves, the use does not reduce the marketability of the copyrighted work, and there is probably not a market for this service that individual copyright holders could monetize. This is a pretty good case for fair use.
By that logic, isn't it the same for Google? They keep a copy of your content in their cache/index (you can even get the indexed page directly from their cache).
So, sure - download to your heart's content. Which means TurnItIn has little incentive to keep works out of their database - you can't make a claim against them if they don't publicize that your work is in it.
You can opt out of that, also it's published content and caching has a carved out exception. When you use this service at a school the teacher submits your paper to the service and they store it to validate against other students papers as well.
They don't only check against "published" sources.
* plagiarism is not generally against the law, although it is a violation of school policies and can get you punished by your school. It's claiming someone else's work as your own. It may or may not involve a copyright violation, it can be plagiarism without involving a copyright violation -- it could be the author gave you permission, or the item isn't in copyright, or it would count as "fair use" -- it's still plagiarism if your teacher/school/honor code panel says it is.
* copyright is about the law, violating a copyright is against the law and can get you civil or criminal penalties. It involves copying work someone else legally owns without permission. It may or may not involve claiming the work as your own, for the most part whether you attribute something properly or claim it for your own is not relevant to whether it is a copyright violation. (I suppose in some edge cases it could be relevant to whether you have a "fair use" defense, but mostly it's not significant in whether something is a copyright violation).
