Through the Looking Glass - S5-E19
Other mistake: Danny supposedly handcuffs an at-risk teenager. When the police officer takes her away to a cell, the girl isn't handcuffed. The handcuffs are just in her hands behind her back. (00:52:00)
Starring: Tom Selleck, Bridget Moynahan, Donnie Wahlberg, Len Cariou, Will Estes
Through the Looking Glass - S5-E19
Other mistake: Danny supposedly handcuffs an at-risk teenager. When the police officer takes her away to a cell, the girl isn't handcuffed. The handcuffs are just in her hands behind her back. (00:52:00)

The Uniform - S2-E11
Character mistake: While handcuffing an auxiliary officer in his apartment, there is a poster on the wall reading, "attention military personal..." Personal is misused. It should read "attention military personnel." (00:16:02)
Frank Reagan: And I don't have a Teflon suit. Everything gets to me. Every time one of ours is hurt, or jammed up, or he's in over his head, it gets to me. I just don't show it, 'cause I can't show it, 'cause nobody wants, or needs, a sensitive police commissioner.
Sid Gormley: OK.
Frank Reagan: So screw you!
Sid Gormley: Yes, sir. That an order, too?
Frank Reagan: Yeah, that's an order.
Sid Gormley: Screw me. I'm on it, boss.
Trivia: In episode 2x22 "Mother's Day" the scene at the start was filmed at Brooklyn's American Veterans Memorial Pier, at Bay Ridge Ave aka 69th St, in Bay Ridge (off Belt Pkwy). The location and design of this pier is distinctive and also sentimental (particularly to older Brooklynites).
Question: What is the significance of the lapel pin worn by detectives on Blue Bloods?
Answer: It is an NYPD Detective Bureau lapel pin. If you zoom in on a pic of "Danny Reagan," you will see that the pin has the letters DB on it.
Answer: It is the lapel pin worn by members of the NYPD Honor Legion.
The lapel pin is on Danny but not Biaz, why? Also, Baker, Sid, Frank &Garrett wear one. Significance? Are they all the same?
Is the P.C.'s pin different than a legion pin? What are the symbols and their meaning?
I think it may be Masonic?
But why would the mayor wear one?