At approximately 35 minutes into the episode, a camera view of street sign showing "9 AV" and "Det. M. O'Connor Way" was seen. This sign is a tribute to NYPD Patrolman William O'Connor who died in the line of duty on Tuesday, May 19, 1931.
The character Chris Johnson is played by actor James Riordan. When Jamie Reagan stumbled into an undercover assignment back in season two, his undercover name was, "Jimmy Riordan." Mobster "Uncle" Phil Sanfino specifically asked Jamie, "You spell that R-e-a-r-d-o-n, or R-i-o-r-d-a-n?" Jamie responded, "R-i-o-r-d-a-n."