The One That Got Away - S7-E13
Visible crew/equipment: After Eddie tells Jamie that she wanted Josh to swoon over her like Caroline seems to be doing with Jamie, when it cuts to Erin as she tells Danny that Child Services will likely release the boy to his parents, as Danny says, "Hold on," the green T-mark is visible on the floor. (00:22:30)
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.