The Corner- the book -Bayliss has while riding with Pembleton,is written by David Simon one of the producers. Charles Dutton directed one of the episode of The Corner. Dutton also guest starred on a previous episode of Homicide.
Detective Meldrick Lewis Clark Johnson is overheard delivering the punchline of the the bawdy "Bear Joke" on three different occasions during the run of the series.. David Simon liked the joke enough, he used it again on The Wire when Sgt. Jay Landsman played by Delaney Williams delivers the punchline ... and the bear says, "you didn't really come here to hunt did you".
Frank Pembleton never draws his gun in his career. The opportunity presented itself when the Homicide Detectives take down Junior Bunk to end the squad room massacre. His second opportunity is when he freezes at Georgia Ray's house and his partner Tim Baylis is shot while shielding him from injury.
Once again Munch dodges a bullet, literally. During the shootout, he is safely in his bar, The Waterfront. He also escaped unharmed in season 3's episode "The City That Bleeds", that saw detectives Howard, Bolander and Felton shot by a fleeing suspect.
During the police station shootout, while everyone is aiming for Bunk, Gharty is too scared to engage. This is consistent with his character, calling back to his first episode "Scene of the Crime", from season 4.