ex *http://www.vancouversun.com/news/bishop+surrender+child+porn+charges/2054526/story.html

"Kealey said generally, custom agents can refer travellers to border officers for a number of reasons, including if the traveller is exhibiting suspicious behaviour, if there is a warrant for their arrest by another law enforcement agency or if they had a past record with immigration and customs officials.


He said a traveller can also be pulled aside if their name is chosen by the CBSA's computer system. He could not confirm if Lahey was chosen at "random," as was previously reported.


"I will tell you that that is a presumption that people have made and it may not be accurate," said Kealey.


During this search, customs officers look through all of a traveller's belongings, including computers, CDs, BlackBerries, cellphones, electronics, mp3 players and luggage.


"It is not simply child pornography that we're looking for. We're also looking for hate literature, obscene material as well," said Kealey. "It could take quite some time."


Travellers could be released and their possessions seized for further investigation — a process that could take up to six months before charges can be laid."


The Canadian border service definitely has it in for Catholic bishops. See
http://community.seattletimes.nwsource.com/archive/?date=19920315&slug=1481109

where Bishop Remi de Roo was caught improperly transporting an HIV positive blood sample on a commercial airline, in his checked baggage no less.