People sometime ask whether it’s proper to cite blogs in a law review article. A few thoughts:
1. Crediting Ideas, Big or Small: Not only is it proper to cite blogs to credit them for their ideas — it’s mandatory, if an observation in your article was borrowed from someone else’s blog post, or even just if the blogger had the original observation first. That’s the same rule as when you borrow from a law review article, an op-ed, or even a personal conversation.
2. But Check with the Author: It’s true that blog posts are often less thought-through than articles or op-eds. (They’re also unedited, but many op-eds aren’t substantially edited by editors, and certainly not by editors who have knowledge of the law; yet op-eds are certainly citable.) It therefore makes sense to check with the author before citing the post, in case the author wants to elaborate on it, or even recant it in some measure — it’s not necessary, but it can be helpful.
3. Supporting Authority: If, however, you’re making an assertion that you want to rely on without proving yourself, and therefore want to cite supporting authority for it — as opposed to giving credit to the originator of an idea, or referring to a particular counterargument that was seems to be present only in a blog post — then you should cite a law review article or a book. Those are the sources that are more likely to be the more thought-through and detailed expositions of the argument.
4. Factual Assertions: Finally, you should not cite blog posts for specific facts quoted or paraphrased by those blog posts, whether they are facts about cases, statutes, social science data, or whatever else. Find, read, quote, and cite the original source instead. But of course that’s true not just as to blog posts but also as to articles, books, and other sources — if they are quoting or paraphrasing another source, you should go to the original. Don’t let the intermediate source’s errors and oversimplifications become your errors and oversimplifications.