Fresh Start - S6-E15
Factual error: The NYPD Sergeant in uniform speaking to Danny only has Sergeant stripes on the left sleeve of his uniform. An NYPD Sergeant has stripes on both sleeves. (00:03:14)
Fresh Start - S6-E15
Continuity mistake: When Erin is in the ladies' room walking toward the door, she finds Anthony "lurking" in the hall, and Erin's eyeglasses which are hanging from her crew-neck top go from facing her right side, to her left side, then back to her right side, between shots. (00:31:55)
Answer: It's a common cop show plot device. If the police on the show always acted in the most logical way (i.e. not alerting a suspect to their presence) the show wouldn't have the opportunity for an exciting foot chase.