Revealing mistake: All the shots of snow falling, mainly when Gunnar is about to be killed, are a very obvious crappy footage of flakes falling projected over the footage of the show. Not a single flake falls on the objects nor the people.
Something Borrowed, Someone Blue - S5-E9
Revealing mistake: When the corpse lies on the bed the pad under the clothes where the thermometer is stuck protrudes.
Trevor Hudson's Legacy - S5-E18
Revealing mistake: There are 2 scenes involving Jessica inside a car. In the first one the car drives calmly as seen from the outside shots, but from the shots inside the car is speeding. When the episode is about to end the car speeds to the police station and now the exact same projection is played, though this time it makes sense.
Chosen answer: This is the very reason my brother and I used to jokingly call the show, "Murder, She Caused." It's amazing she was ever on anyone's guest list for a party, given the likelihood someone would end up deceased. As to your question, most of the time, Jessica Fletcher would have had an air-tight alibi, as she was in a room full of people, or her whereabouts were accounted for when a murder occurred elsewhere. It also seems to me that there were episodes where she, purely with respect to opportunity, could have been a suspect. I believe she even acknowledged that as a logical possibility from time to time, even though she knew, of course, she was not the killer. However, the investigation would obviously rule out the possibility of her involvement, eventually.
Michael Albert