That was "Patches" Kennedy. Teddy Kennedy's son,and the man voted by his peers as being the stupidest member of Congress. He didn't actually kidnap the woman. He just refused to bring the boat ashore so she could leave. He left it anchored offshore,and dove overboard and swam ashore when HE was ready to leave,leaving her alone on the boat. IF I remember right,it was a rented boat,and once he got ashore,he just got in his car and left her and the boat there. This is when she called the USCG to come and take her ashore. The boat rental business charged him a bunch of money because they had to send people down to retreive it.
In the family tradition of swimming off and leaving the poor young woman to fend for herself. (Un)fortunately, this one survived to tell the tale.