In the US there are conflicting precedents at the moment, so it really depends on where the case is being heard. At the moment the case that seems to have the strongest route to the Supremes is the one involving child porn at the border, allowing the court to address both the "are passwords protected" question and the legality of laptop border searches. Unfortunately for the cyberliberty crowd this particular case is the last one they want to see before the court, the facts are not good and it provides an easy excuse for a "law and order" majority on the court to significantly extend the government's reach.