Pittsburgh Phil, real name Harry Strauss, was a real life New York syndicate hitman who worked for the notorious Murder, Inc. He ended up dying in the electric chair in 1941.
Kid Dropper was the nickname of one Nathan Caplin, a New York hoodlum associated with the likes of Lepke Buchalter. He was convicted of a murder in the 1930's and sentenced to prison but made parole in 1937. Two years later he bought the farm himself, a victim of a gangland hit.
Barney says he's been on the police force for 14 years.
One huge mistake by the screenwriter of this episode is that he has characters call Benjamin "Bugsy" Siegal by his nickname to his face. In real life you didn't do that unless you wanted to forfeit some major body parts.
Louis "Lepke" Buchalter was born into a respectable family. He had three siblings who turned out okay. One brother became a physician, a second brother became a rabbi, and his sister became a college professor.
Al Brown was one of the real Al Capone's most frequently used aliases.
Judge Morrison is based on Judge Joseph Crater, a New York judge who disappeared under mysterious circumstances in 1930 while under investigation for corruption. This episode presents a speculative theory as to Crater/Morrison's fate.
KDKA, the Pittsburgh radio station mentioned in this episode, was the first one to begin broadcasting in the United States.
Goof: When the camera pulls out from a closeup of Big Ed who's lecturing Tony for dumping a bar owner's beer, the top of the set can be seen.
The real Dutch Schultz did want to assassinate special prosecutor Thomas Dewey who wanted to proceed with racketeering charges against him. Other mobsters opposed this plan and it probably led to Schultz himself getting gunned down with two of his associates inside a Newark, NJ restaurant in October of 1935.
The character of Nick Joseph appears to be based on Abe "Kid Twist" Reles, a New York torpedo who worked as a hired killer for Murder, Inc. Like Joseph in this episode, Reles later ratted out his employers and also died after a fall from a hotel room window. Reles himself would be featured in a couple of episodes which aired during the final season of The Lawless Years.