Recently, I was studying on search warrants under the Stored Communications Act, 18 U.S.C. 2701, et seq. It is an interesting area of the law for many reasons.
The Act, adopted in 1986, includes some ideas that seem pretty strange now.
In section 2703(a), there is a distinction made between emails that contents of electronic communications that have been stored more than or less than 180 days, as if that makes any sense. I get a lot of email. I keep them longer than 180 days because I can't remember what is in them. Some of them I might keep as long as I have anything, because they are as important to me as my books or photographs. Evidently Congress assumed back then that if any got an important email, they would print it out and delete it after a while to make space for other email. I don't know the theoretical limits on how much email my inboxes could hold, a lot more data than my physical mailbox down by the street that gets clogged with the books and cosmetics and clothes that keeping showing up at the house.
The Act may or may not distinguish between opened and unopened email. I have a lot of unopened emails. They are not very interesting, the ones that go unopened for any length of time. The opened ones are the only ones worth reading, the unopened ones are mostly ads selling clothes or political ideas or travel or sporting goods or whatever else I have ever bought into at least once in my life. I don't read all of my email, and a great deal of it is deleted unread.
The Act provides for subscriber notice in some circumstances and not others. The Government can get an order under section 2705(b) prohibiting the service provider for giving notice to the subscriber. Some providers like Google say they will notify the subscriber if they can. It allows the Government to access content of electronic communications sometimes with a search warrant and sometimes without. The Government never gives notice of its search warrant applications. Remarkably, there is a growing body of case law in which the magistrate judges across the county have taken it upon themselves to deny or modify search warrant applications for the content of emails stored by Google, Microsoft, and other like service providers. The Washington Post published this article about opinions written by a Magistrate Judge in the District of Columbia. There is a law review with the pretty fun title, Let the Magistrates Revolt. There is this remarkable opinion from a magistrate judge in Kansas, and at the other end of the spectrum, this remarkable opinion from a magistrate judge in New York.
There is legislation that seems to have wide support and might get passed to address some of the areas of strangeness. The House of Representatives passed the Email Privacy Act, H.R. 699, in April of this year. The EFF thinks that this act is a historic step in the right direction.