From the link (excerpted):
"More than a dozen people have vanished from cruise ships in the past two years, prompting a Congressional hearing into cruise ship safety last month.
"FBI agent Christopher Swecker said that the agency has investigated 305 serious criminal cases on cruise ships in the past five years. Of those, 10 percent were missing persons and 8 percent of the investigations involved a death on a cruise line."
A couple of years ago, a friend of mine and her husband were not getting along. Then she said they were going to sail on a cruise ship out of Florida for a week.
She is small and he is much bigger and stronger. I advised her not to stand next to her husband at the rail when underway if noone else was around.