Suppose you’re pulled over because your left taillight is out, because your license plate tag is a bit out of date, or because one of your passengers just threw a cigarette butt out the window. And suppose the officer notices that you have a cell phone in your pocket. Should he be able, without a warrant, to look through it like he might look at your wallet photos as you pull out your driver’s license?

One of these very things happened to David Riley, in California. His tags were expired & he was pulled over. It was further discovered that he was driving with an expired license and the police impounded his vehicle. A search of the car turned up weapons and his cell phone, which was seized and searched much as if it was a wallet in a pocket.

A modern wallet (even one made out of duct tape) has the ability to store more or less the same quantity of data as a wallet of yesteryear: Driver’s license, ID card, a few credit cards, a few family photos, a couple of phone numbers on corners of napkins, and some cash.

But a modern size-of-a-wallet smart phone – even though 8 year-olds may be using them to play Angry Birds or to watch Sponge Bob – are a wonder of engineering, with more computing power than the supercomputers that were top of the line not so long ago. When Huey Lewis was singing “The Power of Love,” the most powerful supercomputers of the day would have underperformed the iPhone of today. A smart phone is not just a wallet, for it can store 100,000 wallets-worth of documents.

The Solicitor General of California said that a phone in a pocket is no different than a wallet or a picture in a pocket, even though it would take truckloads to haul around said data in paper form. Hence the case of Riley v. California, which resulted in a conviction on another charge (a gang shooting), based on evidence in Riley’s smart phone. Riley maintains that the Fourth Amendment “right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures,” should have protected him from having all that data in his cell phone seized and examined. The US Supreme Court will be hearing and presumably deciding on this case at a Federal level in the coming months.

We have recently discovered, thanks in part to sources like WikiLeaks and Edward Snowden, that we already live in an era of ubiquitous spying, listening, and observation. Should we then also allow our “papers and effects” stored on our mobile devices to be seized and searched for the static data they contain? To decide, perhaps we should take a look at what these devices do contain, and what a forensic examiner can see in them.

Let’s start with the obvious: pictures & phone books. I’m not a complete pack rat, but my iPhone has about 5,000 photos on it. It also has a couple hundred phone numbers on it, with names, street addresses, email addresses and more. And that’s just my immediate family!

A quick look at my apps and I see more than 200. A lot of those apps store data on my phone, including texts, messages, more pictures – there’s a whole host of stuff. The data stored by the apps on my device include dates, times, durations of events and activities. It stores who I had & who I will have meetings with, and when and where. A forensic examiner can see where I’ve been on the web, what I’ve looked for, what I’ve looked at and for how long.

Then there is less obvious data. The phone stores the names of the networks & wi-fi signals I’ve been attached to and when. The pictures store GPS data so we can see when and where I took a picture, down to a few yards in distance, and fractions of a second in time. So we can see not only where I’ve been on the Web, but where I’ve been in the world.

Notes – pages and pages and pages of notes I seem to have collected. Perhaps hundreds. Voice memos – mine go back 5 years. What’s in all those? I don’t even remember. But I don’t really want to dump them unless I know what I’m throwing away.

Then there’s an interesting item that isn’t even accessible through an app but that forensic examiners love. It’s a dictionary file – not Webster’s, but one deigned by [your-name-here]. It is kind of an informal keylogger. It keeps track of items you type and helps your autocorrect come up with the occasional crazy spelling because you have spelled it that way before. It can be thousands of words long, and several hundred of them are in almost sentence-like form, just as you typed them. You might have typed them in any application – even one that doesn’t store documents, messages, or emails on your phone. You might be surprised at what’s in there.

So you decide – do you want all this info public? Do you want to be pulled over for an expired license tag and have to hand over your phone and all these reams of information to an ambitious and curious law enforcement official who thinks there might be something of dubious legal interest in there? Do you think that there’s nothing on your device that somebody or other might think is indicative of lawbreaking? Or vow-breaking?

That’s the issue the Supreme Court will be dealing with this summer. The SCOTUS will be telling us what the law of the land will be, and whether Gigabytes of your private life could become public. Just. Like. That.

Where do you stand on the issue?

UPDATE: Not ten minutes after I published this article, on June 25, 2014 the Supreme Court’s decision was announced (far faster than the author had expected). It found for Riley and for privacy, that the police must have a warrant if they want to search the cell phone, or other digital device, of an arrestee. Quoth Chief Justice Roberts, “Our answer to the question of what police must do before searching a cell phone seized incident to an arrest is accordingly simple — get a warrant.”

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