The 7th Circuit ruled that police can search your cell phone for your phone number without a warrant. Judge Posner justified this by saying that it wasn’t that big an intrusion.

“On an iPhone without password protection two steps are required to get the number: touching the “settings” icon and then the “phone” icon. On a Blackberry only one step is required: touching the “phone” icon.”

Also, the cop could have just gotten the number from the phone company…

As far as other things the police might see while looking for the phone number?

“It’s not even clear that we need a rule of law specific to cell phones or other computers. If police are entitled to open a pocket diary to copy the owner’s address, they should be entitled to turn on a cell phone to learn its number. If allowed to leaf through a pocket address book, as they are, United States v. Rodriguez, 995 F.2d 776, 778 (7th Cir. 1993), they should be entitled to read the address book in a cell phone. If forbidden to peruse love letters recognized as such found wedged between the pages of the address book, they should be forbidden to read love letters in the files of a cell phone.”

Oddly enough, there’s no real discussion of what happens when the things police find are in fact not love letters, but potential evidence of some crime. Weird!

At no point does Posner even discuss tradeoffs. It’s just “oh, this isn’t that bad.” When he assumes “that justification is required,” he talks about how it’s possible to remotely wipe the phone. Almost as if the Fourth Amendment is designed to ensure the police have access to evidence, rather than to protect citizens. Sigh.

Opinion here.