As of today, it is illegal to possess or deal in shark fins in the state of Hawaii.
Now for the rest of the country. As usual, the House has long since passed the Shark Conservation Act but the Senate sits on its thumbs, far too busy doing nothing else to be bothered. Tell them to pass S. 850.
You could start with urging the members of the Commerce, Science, and Transportation Committee to get a move on. Committee members Boxer and Cantwell are already sponsors, as are, happily, the other four west coast senators.