Sympathy for the Goddess - S2-E17
Plot hole: Charlotte tells Chloe that she was talking to the man on the phone when she hears gunshots. Being a veteran detective Chloe should have noticed since the man's gun was in his pocket (Chloe comments that his phone was found on him) that he couldn't have been using it when he was shot, therefore Charlotte was lying. Yet she never realised this.
Answer: Boo Normal and Once Upon a Time were going to be part of season 4, then the show got cancelled (before being picked up elsewhere). As such they were added on to the end of season three as "bonus" episodes, hence the continuity being off. But not really a mistake, just a quirk of broadcasting. Boo Normal was originally going to be between the episodes "High School Poppycock" and "Infernal Guinea Pig" in season 3 before being slated for season 4, presumably because aside from the point you've raised, it was fairly flexible, continuity-wise.
Jon Sandys ★