Ruta Lee was more than 25 years younger than the two actors playing the men with which her character is involved in this episode (Philip Bourneuf and Walter Coy). Asa Culver mentions to Perry Mason that his wife is several years younger than him.
Per various car registrations in the series, the same license plate number (NFL 252) has been seen, or will be seen, five times for five different characters. The episodes are The Case of the Bartered Bikini (1959), this one (The Case of the Prudent Prosecutor (1960)), The Case of the Mythical Monkeys (1960), The Case of the Crying Cherub (1960), and The Case of the Barefaced Witness (1961).