A member of Cruise Critic posted a photograph of some kind of device designed to prevent the insertion of a key card to unlock a passenger cabin door as well as to padlock the door handle from moving. The passenger apparently sailed aboard an unidentified Royal Caribbean cruise ship last month, and invited the fellow Cruise Critic members to speculate on why this device was used. Was the device used to lock a passenger in the cabin? This seems very unlikely. Or was the device used to keep the cabin secure for an investigation by law enforcement officials to search for drugs or to investigate a crime scene? Aren't these cruise ship doors designed such that there is a master lock or key which can prevent cleaning personnel out of the cabins following crimes? What happened on the Royal Caribbean cruise ship at the end of last month? Which cruise ship was this (some speculate the Liberty of the Seas or the Monarch of the Seas )?