The video you just saw was a whirlwind tour of the world of police surveillance. You saw accounts of facial recognition, predictive policing, the use of CCTV, the use of social media accounts to find out what people are up to, and a host of other surveillance techniques. The world of police surveillance is growing and it's becoming fascinating, but at the same time perhaps a little bit concerning to those who are worried about invasions of privacy. So, that's what we're going to talk about today is police surveillance or various kinds of police surveillance techniques that are being developed that are being used to investigate crime. Again, you've seen a lot of examples, some other examples Geo tracking, use of planes to track individuals using cameras, and a number of other kinds of devices. So, what I'm going to be focusing on is the law that regulates this technology, the law that regulates this surveillance. In particular, we're talking about the Constitution, the Fourth Amendment. Now, in the last lecture we talked about the Fourth Amendment which regulates searches and seizures. We'll do a little bit more talking about that today. The last lecture we focused mostly on the seizure part of the Fourth Amendment. We talked about stops and arrests, and use of deadly force. Today, we're going to talk about the search part of the Fourth Amendment. But interestingly enough, even though one might think that everything in the video and when I just mention involves some kind of search by the police. That's not what the Supreme Court says. The Supreme Court has defined the word search very differently than you or I might define the word search for constitutional purposes. So, let's start with an example. Let's just start with a hypothetical situation. Let's assume the officer Smith who you see here in the year 2020 stops a car for traffic violation. It turns out the person driving the car is a person named Omar Abdullah. Now, Abdullah's rush registration license check out. Everything's fine legally speaking. But, Abdullah seems a little bit nervous to officer Smith. So after Smith goes back to a squad car and he gets out as Raytheon Electromagnetic Scanner. What does this do? It scans cars for weapons, for bombs. Now, nothing shows up on the scanner. So again, Abdullah checks out. But Smith is still a little bit suspicious. So what does he do? He gets Abdullah's phone number and he knows that with the phone number Abdullah can be tracked using cell phone technology. That's exactly what the New York Police Department does. They follow Abdullah in real time for the next couple of weeks. They also watch Abdullah as he takes walks from his apartment using CCTV cameras that are positioned on buildings and phone poles around the New York City area. Their interest becomes peaked when they noticed that Abdullah goes not to only to his own mosque, but to a number of other mosques as well. So now they become very interested, and they decide to get more information about Abdullah. So what do they do? They requisition his bank records and his phone records to see about his financial transactions and his communications. They also get a hold of other records that are available through third parties, including through a company named Choice Point. Choice Point is a private company which tries to accumulate information from public and quasi public records and then sells it to the government, and in this case the government decides to buy records having to do with Abdullah. Finally, because Abdullah tends to not close the curtains on his windows, the police set up a Startron from in an apartment across the way to see what they can see through Abdullah's windows. So this is a whole bunch of surveillance. This is a lot of surveillance activity by the police. Now, it could be that Abdullah is terrorist, it could be he is not a terrorist, but simply an illegal immigrant, it could be he's totally innocent. I'm going to leave you hanging right now as to what Abdullah is or is not. The point I wanted to make is that nothing you see here is regulated by the Constitution. Not a single surveillance techniques that I've described is regulated by the Constitution. Now, the key constitutional provision, here, as I've already mentioned, is the Fourth Amendment. As we talked about the last lecture, the Fourth Amendment prohibits unreasonable searches and seizures of houses, persons, papers, and effects as you can see from the language. So that's the key provision that we are going to be talking about. There's a little bit more to the Fourth Amendment though I want to acquaint you with. The rest of the Fourth Amendment says, "No warrants shall issue, but upon probable cause, particularly describing the place to be searched and the persons or things to be seized." So what you've just seen is about 47 words thereabouts. That set of words comprise the entire regulatory regime that the Constitution imposes on search and seizure in by the police. Those 47 words alone are the words that we derive most of the case law that regulates police search and seizures. Now, what does that language mean? As we talked about in the last lecture, the word probable cause is very important. The word probable cause if it had to be quantified, probably it'll be quantified at roughly a more likely than not level of certainty around the 50 percent level of certainty. Now, this probable cause has to be found by a magistrate if there's time to get a warrant. If there isn't time we get to warrant and magistrate finds there's probable cause, the magistrate will issue a warrant authorizing the search. Now, in the police actions we talked about in the last lecture stops and arrest, there usually is not time to get a warrant. So we didn't talk much about warrants during the last lecture. But in this situation, Abdullah's case there is time to get a warrant for the kinds of things that police engaged in. So typically, if the Fourth Amendment applied, the police will have to get a warrant from magistrate based on probable cause. So, that's the Fourth Amendment. However, it does not have, as I said before, any impact on what the police did in Abdullah's case. Now, why is that? It's because Fourth Amendment precedent is mired in an era when searches were physical in nature. In the last lecture, we talked about some of those kinds of searches and seizures. For instance, a stop is a physical action by the police. So is an arrest. Searches also usually involves some kind of physical intrusion, going into someone's house, searching someone's car, maybe rifling through someone's papers. But today, with the advent of technology that can see through walls, that can monitor public activities 24 hours a day, seven days a week, that can surveil literally millions of records in mere seconds, police are resorting increasingly to what I call Virtual Searches. What are virtual searches? Well, they don't require physical intrusion. The officer can sit at his or her desk tracking cars, getting digital information financial phone records and that kind of information without leaving the office simply at a touch of a button. So that's what I call a virtual searches. No physical intrusion involved, and these searches can often be done covertly. That is without the knowledge of the individuals being affected. As you can tell from Abdullah's case, this kind of virtual search it can drastically change the way police carry out their typical investigative activities. So, why hasn't the Supreme Court said much about this kind of surveillance? Why does a Fourth Amendment not regulate the kinds of things we saw in Abdullah's case? Well, the principal culprit is the first word you see here, the word search. Remember, the Fourth Amendment prohibits unreasonable searches and seizures, a lot rides and what a searches, and the Supreme Court has never defined the word search the way a lay person would define, the way you and I would define it as looking for something or examine something instead it's defined it the way you see here. A search is a police action that infringes an expectation of privacy the society is prepared to recognize as reasonable. Now, as first construed in the case of Katz, you see I cited down here at the bottom, this language was interpreted pretty broadly. It was defined pretty broadly. In Katz itself, the police had bugged a phone conversation and the court said the Fourth Amend applies to that situation. Even though a conversation does not house person, paper, or affect, the four items that are mentioned in the Fourth Amendment. Furthermore, what they did in order to get Charlie Katz's conversations, they bugged the phone booth. A phone booth is also not a house person, paper, or effect. Yet the court said the Fourth Amendment applied in that situation. Well, that's a fairly expansive interpretation of the Fourth Amendment. But since Katz, the court is made very clear at the Fourth Amendment is to be applied narrowly. Yes it does apply when the police intercept a phone conversation or the content or an email communication non conceptually, then the fourth term it does apply. But in every other situation, including those we saw in Abdullah's case, the Fourth Amendment does not apply. Typically, what the court has done is limiting the Fourth Amendment application outside of the phone bugging and email bugging contexts to situations involving physical intrusions. Unless there is a physical intrusion, there is no Fourth Amendment search. In other words, it's still adhering to the precedent I was talking about earlier. Now, how has the court arrived at this narrow definition of the Fourth Amendment? Well, it's done so through three, actually four different doctrines. You can see them here, the knowing exposure doctrine, the general public use doctrine, the contraband-specific doctrine, and the assumption of risk doctrine. When we come back, we're going to talk about these four doctrines and discuss how they've been defined to narrow the scope of the Fourth Amendment. But I'm curious before we take a break if there any questions about what I've said so far. Yes? So in the case of the phone booth, I mean I guess he wasn't specific hearing for that person who was talking on the phone with, but what about everybody else who used the phone previously. Right. So, because a Fourth Amendment applies to that phone call what the police should've done. They did not do what they should've done is gone to magistrate and prove to the magistrate there's probable cause probably the phone conversations that we're going to intercept would be evidence of criminal activity. They probably had a pretty good hunch, that Charlie Katz was going to be involved in a phone call involving illegal activity. In fact, they knew he was a gambler, a bookie. So they probably had they gone to magistrate could have gotten war based on probable cause, but they didn't do so and therefore the search was illegal. But that one would only allow them to intercept Charlie Katz's calls, not anyone else calls. Yes? So, when the man was pulled over the policemen decided to investigate into him more because he seem too nervous and I feel like that's something that normal response for getting pulled over. Is there anything in the constitution that text people from that kind of discriminatory selection? Well, that's an interesting question. The last class we talked about the extent to which please use traffic violations to engage in what are sometimes called retextual actions. In other words, they don't really care about the traffic violation. They want to investigate the person for similar reason that might have been what was going on in this case. So, those are hypothetical I can actually make up. That's what's going on in this case or I can say no it's not what's going on in this case, but it can happen. Typically, if the police actually physically searched the car, based solely on the fact individual's nervous without any kind of consent, that would be a violation of the Fourth Amendment. Why? It's a physical intrusion into the car. The point I was making in Abdullah's case is there was no physical intrusion. The cop did not go into his car. Yes, he did scan the car with the Raytheon device, but that's not a physical intrusion. Yes, they tracked the car with cell phone signals, but that's not have physical intrusion. So that's why, and we'll will go into this more in a second, that's why the Fourth Amendment doesn't apply. So we'll take a break now and when we come back, we'll talk about these four doctrines.