Most scientific journals involve "peer review," where the peers in question are supposed to be experts on the subject of a particular submitted article. Because reviewers' time is scarce, the presumption is that a paper submitted to a peer reviewed journal is not currently being submitted anywhere else. The author submits the paper, and waits for a review (either a rejection, a revise-and-resubmit, or an acceptance). Depending on the field and the journal this can happen quickly, or (for economics journals) slowly.
Law Reviews are different. Authors submit to multiple journals simultaneously, and the papers are reviewed not by peers but by the third year law students who edit that year's edition of their law school's Review. And well-received authors don't get "acceptances" they get "offers" to publish, which typically have a short deadline, e.g. 24 hours. In that time they can contact one of the other law reviews to whom they have submitted the paper and try to get it accepted there.
For example, the submissions page of the University of Chicago Law Review has the following invitation to ask for an Expedited Review: "If you have received a formal offer of publication from another journal and would like to receive an expedited review by the University of Chicago Law Review, please contact us at lrarticles[at]law.uchicago.edu. When requesting an expedited review, please put "Expedite" as the subject of your email and include in the text:
1) The author name and title of your manuscript; 2) The name of the journal that has extended an offer to you; 3) The date that the offer expires; 4) The phone number or email address of a contact person at that journal;5) An electronic attachment of your article (plus C.V. or cover letter) to facilitate and accelerate the process. The University of Chicago Law Review will attempt to honor all requests for expedited review for which the above information is provided. ..."
But there is an experiment afoot to change the way law review articles are reviewed, and to try to have peer review while still allowing authors to submit to multiple journals simultaneously: Mainstream law review tries peer review
The idea is to have the reviews done first in a clearinghouse called the Peer Reviewed Scholarship Marketplace "The Peer Reviewed Scholarship Marketplace (“PRSM”), a consortium of student-edited legal journals, exists to provide student-editors with peer evaluations of legal-scholarship manuscripts and to assure the publication of quality articles. PRSM connects authors and journals with subject matter experts, who through their reviews provide editors with the information they need to make informed decisions regarding article selection. With PRSM, the future of legal-scholarship publishing has arrived."
"The Peer Reviewed Scholarship Marketplace (“PRSM”) began with the South Carolina Law Review’s Peer Review Pilot Program... Numerous authors submitted manuscripts to the South Carolina Law Review, and many other legal scholars and practitioners volunteered to serve as peer reviewers. Relying on the reviewers’ evaluations, the South Carolina Law Review chose three articles for publication in a special Peer Review Issue (Volume 60, Book 4). This special issue also featured a favorable foreword by Judge Richard A. Posner as well as an essay describing the South Carolina Law Review’s experience with peer review.
The Pilot Program’s success encouraged the creation of PRSM, a consortium of student-edited legal journals that believe that peer review can enhance the quality of the articles that journals select and ultimately publish. PRSM works much like the familiar manuscript submission vehicle ExpressO but with a peer review component. Authors submit their work exclusively to PRSM, whose administrators then arrange for double-blind peer review of each manuscript. After six weeks, PRSM members will receive a copy of the article with the reviews, which will assist the student-editors in publication decisions. As with ExpressO, members will make their own independent offers to authors, who are free to accept or decline. If an author is unsatisfied with all offers—or receives none after a designated date—he or she is free to resubmit his or her reviewed manuscript through ExpressO or another preferred vehicle.
PRSM thus benefits all parties: authors, reviewers, journals, and the legal community that relies on scholarship published in student-edited journals. All authors receive valuable feedback from their peers, and successfully placed authors further benefit from the “peer reviewed” certification of their published manuscripts. Reviewers are offered an opportunity to comment on new scholarship pertinent to their areas of expertise and thereby participate in the “gate-keeping” article selection process. Student-edited journals are given an additional tool to spot and select the most novel and valuable research for publication. Finally, PRSM’s peer review process produces higher quality scholarship for the legal community that reads and relies on the profession’s journals.
For more information about South Carolina Law Review’s experience with the Peer Review Pilot Program and creation of PRSM, go here."
Apparently law journals in the UK are more like economics journals than like American law reviews, in that authors can only submit to one journal at a time, and submissions are peer reviewed (see Comparative journal submission experiences by John Ip).
In the meantime, a peer-review holdout in the sciences is moving to peer review. The Proceedings of the National Academy of Science, the journal published by the honorific society from which it takes its name, had a tradition of allowing NAS members to "communicate" papers without a refereeing process. For some time now that has coexisted with a peer review process; some papers are reviewed, others simply communicated. Next year that will come to an end, and all papers will be reviewed: PNAS will eliminate Communicated submissions in July 2010.
The problem is that communicated papers were apparently of very uneven quality. (Some biologists I know claim that PNAS stands for "post-Science and Nature," as papers are only sent there after being rejected by those two other journals.) And while there is a very sensible scientific tradition of simply ignoring bad papers, some of the ones that appeared were apparently embarassing: Peer Review Failure?
Peer review is undoubtedly a part of the answer to the larger question about why journals persist at all given the growth of the internet: Why Hasn’t Scientific Publishing Been Disrupted Already?