The wake scene for Detective Ray Cole was a tribute to producer Robert F. Colesberry, who played Cole and who had passed away in February of 2004.
Former Baltimore City Police Commissioner Ed Norris had a recurring role playing homicide detective Lt. Norris. He was convicted of 2 counts of federal corruption in a plea agreement over dubious charges with many political implications. Following the taping of Dead Soldiers S03E03 he would serve a six month sentence in a federal prison. Upon his return, he would resume his role as Lt. Norris.
At the end of Dead Soldiers, Councilman Thomas 'Tommy' Carcetti is seen having an extra marital affair at a political fund raiser. The character Tommy Carcetti bears a strong resemblance to former Baltimore Mayor/City Councilman and Maryland Governor Martin O'Malley. This scene caused quite a kerfuffle at the time.
The theme of this season - the legislation of drugs in certain quarters of the city - is first articulated in this episode.
From this point on, the main focus of the series shifts heavily from police work to city politics of Baltimore.