Glenn Cannon, who appeared as a semi-regular in this series as District Attorney John Manicote, was in this episode (uncredited) as a crook pretending to be a teacher.
When McGarrett has Pierce's professor friend Jordan visit the hotel room, he mentions the is room 234. But the room number on the telephone in Pierce's room is 259.
The scene where a police car passes people attending church is a stock shot from the season 2 show "Savage Sunday".