The new policies, replacing guidance from 2009, clarify government search powers when it comes to such devices, which have exploded in both use and capability in recent years. The policies place some new restrictions on how extensively electronics can be searched, but still give latitude to US officials.
The government has wide legal authority to search the belongings without a warrant of travelers at the border -- a term that applies to all entry points to the US from abroad. The new policy offers guidance to US officials on to what extent, however, they can search the personal electronic devices of all travelers entering and exiting the country.
The move comes amid heightened anxiety under the aggressive border policies of the Trump administration as well as recent court decisions limiting the government's reach into ubiquitous personal electronic devices.
Under the new policies, agents are allowed to search electronic devices at the border for "information stored on the device" that is accessible through software on the device, DHS said.
But officers cannot use the device to access data stored beyond the device -- a clarification that is in line with concern from appellate courts and the Supreme Court about the extensive amount of personal information that is accessible through personal devices.
Officers shall ask travelers to either put their devices in an offline mode or disable their network connectivity, the document states, and "take care to ensure" they make no changes to content on the device.
There are exceptions, however. The guidance states if there is "reasonable suspicion" of law-breaking or a national security concern, and with approval from supervisors, officers can conduct a more advanced search.
The guidance also allows officers to request traveler's passcodes and to detain a device that is encrypted or inaccessible for further review.
The policy continues to include information about how to handle information that could be privileged, like an attorney-client communication, and states that any detention of such a device should not exceed five days in normal circumstances. There are detailed instructions on retention of information, whether it needs to be deleted later, and how to document and report what happened.
CBP called border searches "essential" to enforcing the law and national security.
"CBP is committed to preserving the civil rights and civil liberties of those we encounter," Deputy Executive Assistant Commissioner of Field Operations John Wagner said in a statement. "CBP's authority for the border search of electronic devices is and will continue to be exercised judiciously, responsibly, and consistent with the public trust."