Factual error: Marie is a female name. Therefore, the island should be Sainte Marie, not Saint.
Episode #2.7 - S2-E7
Continuity mistake: When Fidel and Dwayne arrive at the place where Camille and Richard are hiding for the hurricane, they can open the doors without a problem, whereas Camille and Richard had taken great care of locking the doors from the inside.
DI Jack Mooney: Strictly speaking, paradise is a state of mind. You know that, right? I mean, the dung beetle - very different idea of paradise, doesn't he? (00:48:25)
More trivia for Death in Paradise
Question: Why don't they even think of pretending the victim just drunkenly tripped in the kitchen while getting a sandwich, and his sister-in-law reflexively tried to catch him, unfortunately holding a knife? He thought he would live a few more minutes, so he could have backed up the story. Instead, everybody (victim and police) just takes it as given that the stabbing will reveal their relationship.