This DHS rule meant that they could search all your electronics (phone, laptop, etc) if you were within 100 miles of a border. This court decision is at least a partial rejection of that rule, at least in so far as the Ninth Circuit area is concerned (see map).
Via CNET:
U.S. customs officials must have a reasonable justification before snatching your laptop at the border and scanning through all your files for incriminating data, a federal appeals court ruled today.
The Ninth Circuit Court of Appeals ruled that Homeland Security’s border agents must have “reasonable suspicion” before they can legally conduct a forensics examination of laptops, mobile phones, camera memory cards, and so on.
Today’s opinion (PDF) is a limited — but hardly complete — rejection of the Obama administration’s claim that any American entering the country may have his or her electronic files minutely examined for evidence of criminal activity. Homeland Security has said the electronic border searches could detect terrorists, drug smugglers, and people violating “copyright or trademark laws.”
It’s only a limited rejection because certain warrantless searches at the border remain permissible: The judges said that “a quick look” or “unintrusive search” of a laptop, such as asking its owner to turn it on and peruse open windows, is perfectly OK. In addition, the court indicated that previous criminal history qualifies as “reasonable suspicion” that justifies a complete forensics analysis.