In addition to the episode title's reference to "Cowardly Lion," other references to "The Wizard of Oz" in this episode include the name of the baby gorilla (Toto), a sign in the San Diego Zoo pointing to "Lions, Tigers, Bears," and the first two initials of actor O.Z. Whitehead, who plays a key supporting character.
Paul Birch, cast here as Security Officer Crawford, played Perry Mason creator Erle Stanley Gardner in the short-lived series, The Court of Last Resort (1957).
Twice by Perry and once by the Judge, the DA (Paul Langton) is called Mr. Telford. But in the credits Paul Langton's character is Prosecutor Green.
O.Z. Whitehead (appearing as Harry Baucom) and Eddie Quillan (as bookkeeper Abner Keller) appeared together in the 1939 classic film, The Grapes of Wrath (1940). Whitehead played Al Joad and Quillan appeared as Connie Rivers, the brother-in-law of Al and Tom Joad (Henry Fonda).