Continuity mistake: The pad where the knife is stabbed protrudes under the writer's shirt.
Funeral at Fifty-Mile - S1-E22
Continuity mistake: When Jessica walks from the house to the barn at the end, she is wearing knee high brown boots. By the time she reaches the barn they have been replaced with court shoes.
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: When Jessica's publisher at the beginning of the party holds her hand and kisses it, he is holding her hand in different ways in the separate shots. (00:18:20)
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: Mr. Giles holds the telephone as he interrogates the private eye, who answers in a rather defiant way to the threat of "the local constable" getting involved. So Giles puts the receiver down, but notice that in the first shot he is passing it from the right to the left hand. In the close-up it is the right hand to hang up, though. (00:23:15)
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: During the scene at the train station, Jessica's nephew introduces to her Kitt Donovan from the publishing company. Just as he says "in public relations", a man pops in the foreground - it is an extra that walks out of the rail car. In the reverse shot that follows, the same extra is only then coming out of the train. (00:09:35)
The Murder of Sherlock Holmes - S1-E1
Continuity mistake: Episode 1-0, "The Murder of Sherlock Holmes"; Mr. Giles opens the door of the antechamber of his office, finally putting an end to Jessica's long wait. Grady right away at the first click of the lock takes his hands off his pockets and tidies up his sleeves. But in the next shot when Grady actually enters and talks to the secretary, Grady is still with his hands on his pockets repeating the gesture. (00:10:10)
Continuity mistake: When Ron Moody runs into the sea in pursuit of a suspect trying to escape, he shouts at Jessica to "Get the package!" In the next shot we see Jessica reluctantly follow him in, with a clear waterline from a previous take showing on her dark overcoat/cloak.
Continuity mistake: After Kellijian aims to choke his wife, they kiss. Right afterwards, the position of her left arm on his body is not continuous between shots.
Continuity mistake: Lew Feldman picks up his cigar from the ashtray, but an instant later, it's back on the ashtray.
Continuity mistake: When Patti is shot, Barry kneels down, places his face against hers, and lies on top of her. A shot later, from a different angle, he is away from her, repeating all previous movements.
Continuity mistake: When the robber is killed, his hat falls off. A shot later, it's back on.
Continuity mistake: When Jessica (a stunt double) rides her bicycle at the start, her red scarf is tied around her waist. A shot later, when the real Jessica is shown, the scarf hangs around her neck.
Continuity mistake: When Jessica talks to Lt. Bergkamp, she takes her left hand to her ear to improve her hearing, but from the opposite shot, her hand is lowered.
Continuity mistake: Before Joan leaves the restaurant, she has a glass of wine on her right, but from Jessica's POV, the glass has moved to Joan's left side. Also, Jessica's glass is in front of her, but moves to the right side of the table after Joan leaves.
Continuity mistake: When Bud and Andy arrive at Cagliostro's table, Jessica stares with her glasses on, while Joan turns her head around. An instant cut later, Jessica's glasses are off and Joan is turning her head again.
Continuity mistake: When Jessica is having dinner with Joan, Jessica's right arm is either extended on the table next to the cutlery or not, depending on the shot.
Continuity mistake: When Joan leaves the restaurant, her glass is full. Next time we see it, it's empty.
Death Takes a Curtain Call - S1-E9
Continuity mistake: When Jessica and the Russians escape in the Rolls Royce, the back projection is not continuous between shots. On the right side window, the place swaps between a modern city and a park. On the left window, the same people walking around are played several times.
Continuity mistake: Patti and Brian enter the alley, talk to the card scammer, and keep on walking. From a different angle, they're metres behind, entering the alley again.
Continuity mistake: When Grady introduces the understudy, he puts his arm around her shoulders. A shot later, his arm is away.
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