Statistically speaking, the majority of cruise ship sexual assault cases are perpetrated by cruise ship employees. But passenger-on-passenger crimes do take place as well. For example, last November a Royal Caribbean passenger reported that she had been sexually assaulted by a fellow passenger while sailing on a cruise to Vanuatu.
The woman reported to the staff that she had been sexually assaulted by a fellow passenger, prompting them to call the authorities. When the ship returned to Sydney, Australian police were waiting to board the vessel and investigate.
So, what is the protocol when a passenger reports having been sexually assaulted by a fellow passenger? Interestingly, after reading hundreds of cases involving cruise ship sexual assault, cruise companies seem to take the passenger-on-passenger cases more seriously, in general. That is to say that reports of passenger-on-passenger cases often result in the authorities being called, and someone being arrested, or at least detained for questioning.
But cases of crew member-on-passenger attacks often include reports of the perpetrators essentially being dropped off at their home countries, and thereby avoiding prosecution. These kinds of cases happen far more often than perhaps would be imagined, such as when a cruise ship worker was dropped off at his home country after he kissed a young girl, and was caught on surveillance camera, and when a crew member was dropped off at his home country after having told a passenger that he wanted to rape her.