Visible crew/equipment: When Eddie comments that the Rough Tough Cream Puff made a collar, she and Jamie walk up the hallway, and before Eddie reaches the doorway we can see the red tape mark on the floor as we hear Marcus brag, "mad fast." (00:15:55)
Visible crew/equipment: After Frank tells Garrett to set up the meeting with Thomas and agrees to play nice, when it cuts to Erin as she walks toward Zach and the AG, the T-mark and white tape mark are visible on the floor in front of the two men. (00:01:50)
Visible crew/equipment: Towards The End of the episode as ADA Reagan is walking to her car, you can see the cones in the DAR end of the street the filming crews used for traffic control to keep traffic off the set. (00:02:30)
Visible crew/equipment: At the start of the episode, the first character (Cole) has an audio wire sticking out the back of his suit. It disappears in the next shot. (00:00:25)
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.