The handcuff scene from 'Who Done It?' is used again in 'Abbott & Costello Meet Captain Kidd'. This time Captain Kidd demonstrates to Oliver how handcuffs should be worn by putting them on himself.
When Guybrush calls himself to the stand, he can say, "Where were you on the night of August 15th?", which is a spoof on Lou Costello's line, "Where were you on the night of January 16th?" while he is interrogating the radio show cast in the 1942 film, "Who Done It?"