However, bringing a clean laptop means more than simply dragging files into the trash. Deleting files will not remove them from your hard drive. See our software and technology article on secure deletion for details.
Another solution is to use password-based disk encryption to prevent border agents from being able to read your files. The consequences of refusing to disclose a password under those circumstances are difficult to predict with certainty, but non-citizens would face a significant risk of being refused entry to the country. Citizens cannot be refused entry, but could be detained until the border agents decide what to do, which may include seizing your computer.
Stop and frisk searches. The police can stop you on the street and perform a limited "pat-down" search or "frisk" — this means they can feel around your outer clothing for concealed weapons.
The police don't need probable cause to stop and frisk you, but they do at least need to have a reasonable suspicion of criminal activity based on specific facts. This is a very low standard, though, and the courts usually give the police a lot of leeway. For example, if a police officer is suspicious that you're carrying a concealed weapon based on the shape of a lump under your jacket or the funny way that you're walking, that's usually enough.
If, while patting you down, a police officer feels something that he reasonably believes is a weapon or an illegal item, the officer can reach into your clothes and seize that item. Search Incident to Lawful Arrest
Search Incident to Arrest (SITA) doctrine is an exception to the general requirement that police obtain a warrant before conducting a search. The purpose of this exception is to protect the officer by locating and seizing any weapons the person has and to prevent the destruction of any evidence on the person. According to the SITA doctrine, if an arrest is valid, officers may conduct a warrantless search of the arrestee and the area and objects in close proximity — i.e. the "grab area" — at about the same time as the arrest.
Officers may also perform inventory searches of the arrested person at the time of the arrest or upon arrival at the jail or other place of detention.
So, the police are allowed to search your clothing and your personal belongings after they've arrested you. They can also search any area nearby where you might conceal a weapon or hide evidence. If you are arrested inside a building, this usually means they can search the room they found you in but not the entire building. If you are arrested while driving, this means they can search inside the car, but not the trunk. But if they impound the car, then they can search the trunk as part of an inventory search. This is another example of the way that multiple exceptions to the warrant requirement can combine to allow the police a lot of leeway to search without going to a judge first.
When searches are delayed until some time after the arrest, courts generally have allowed warrantless searches of the person, including containers the arrestee carries, while rejecting searches of possessions that were within an arrestee's control. These no longer present any danger to the officer or risk of destruction because the arrestee is now in custody.
The question remains whether the SITA doctrine authorizes warrantless searches of the data on cell phones and computers carried by or located near the arrestee. There are very few cases addressing this question. In one case in Kansas, for example, the arresting officer downloaded the memory from the arrestee's cellphone for subsequent search. The court found that this seizure did not violate the Fourth Amendment because the officer only downloaded the dialed and incoming numbers, and because it was imperative to preserve the evidence given the volatile, easily destroyed, nature of cell phone memory.
In contrast, in another case in California, the court held that a cellphone search was not justified by the SITA doctrine because it was conducted for investigatory reasons rather than out of a concern for officer safety, or to prevent the concealment or destruction of evidence. The officers could seize the phone, and then go obtain a warrant to do any searching of it. The decision rejected the idea that the data searched was not private, in light of the nature and amount of information usually stored on cell phones and laptops.
If the police arrive at your home or office with an arrest warrant, go outside, lock the door, and give yourself up. Otherwise, they'll just force their way in and arrest you anyway, and then be able to search nearby. It is better to just go peacefully without giving them an excuse to search inside.
If you are arrested, the officers are going to seize all the property on your person before you are taken to jail. If you have a cell phone or a laptop, they will take that too. If you are sitting near a cell phone or laptop, they may take those as well. The SITA doctrine may allow police to search the data. It many also allow copying for later search, though this is well beyond what the SITA doctrine's original justification would allow.
You can and should password protect your devices to prevent this potentially unconstitutional privacy invasion. But for much stronger protection, consider protecting your data with file and disk encryption.
Prudent arresting officers will simply secure the devices while they get a warrant. There's nothing you can do to prevent that. Do not try to convince the officers to leave your phone or laptop behind by disavowing ownership. Lying to a police officer can be a crime. Also, prosecutors may use your statements against you later to argue that you do not have the right to challenge even an illegal search or seizure of the device, while still being able to introduce information stored on the device against you.
In addition to search warrants, the government has another very powerful legal tool for getting evidence — the subpoena. Subpoenas are legal documents that demand that someone produce specific documents or appear in court to testify. The subpoena can be directed at you to produce evidence you have about yourself or someone else, or at a third party to produce evidence they have collected about you.
Subpoenas demand that you produce the requested evidence, or appear in court to testify, at some future time. Search warrants, on the other hand, are served and executed immediately by law enforcement with or without your cooperation.
Subpoenas, unlike search warrants, can be challenged in court before compliance. If you are the recipient of the subpoena, you can challenge it on the grounds that it is too broad or that it would be unduly burdensome to comply with it. If a judge agrees, then the court may quash the subpoena so you don't have to produce the requested evidence. You may also be able to quash the subpoena if it is seeking legally privileged material, or information that is protected by the First Amendment, such as a political organization's membership list or information to identify an anonymous speaker. If the subpoena is directed to a third party that holds information about you, and you find out about it before compliance, then you can make a motion to quash the subpoena on the grounds of privilege or constitutional rights regardless of whether the third party decides it would otherwise comply. However, you have to do so before the compliance date. Subpoenas that are used to get records about you from third parties sometimes require that you be notified, but usually do not.
Subpoenas are issued under a much lower standard than the probable cause standard used for search warrants. A subpoena can be used so long as there is any reasonable possibility that the materials or testimony sought will produce information relevant to the general subject of the investigation.