- This article is part of a series on Litigation
A preliminary injunction is a remedy ordered by a court prior to the final determination of the merits of a legal case. It is used in order to restrain a party from going ahead with a course of conduct, or alternatively is used to compel a party to continue with a course of conduct, until the case has been decided.
In the context of FOIA requests, plaintiffs may seek a preliminary injunction by way of attempting to expedite the processing of their request.
Where injunctive relief is sought, the court will not concern itself with the parties' substantive claims, but instead will assess:
- whether the plaintiff is likely to prevail upon the merits
- whether the plaintiff will be irreparably harmed absent relief
- whether the defendant will be substantially harmed by the issuance of injunctive relief, and
- whether the public interest will be benefitted by such relief 
In cases where injunctive relief has been granted, a key element has been the court's finding of an "exceptional and urgent need" for disclosure of the requested information.
- Judicial Watch, Inc. v. DHS, 514 F. Supp. 2d 7, 11 (D.D.C. 2007)
- For example, see Cleaver v. Kelley 427 F. Supp. 80 (D.D.C. 1976) in which the court issued a preliminary injunction requiring, within 21 days, the production of all documents responsive to a FOIA request and the filing of an index detailing and justifying any withholdings. See also Aguilera v. FBI 941 F. Supp. 144 (D.D.C. 1996) in which the court granted plaintiff’s motion for a preliminary injunction and ordered the agency to “comply with plaintiff's FOIA requests” and file a Vaughn index within 30 days.