Throughout the series, Perry's office telephone # was Madison 5-1190; Della's was Hollywood 2-1799.
Carl Betz, who plays Dr. Chandler, would later star in two series: the iconic The Donna Reed Show (1958), where he also played a doctor, and Judd for the Defense (1967), where he was a defense attorney.
Walter Reed and John Pickard play detectives together here. They played G-men together in Government Agents vs Phantom Legion (1951).
When Perry Mason is summoned to the grand jury, there are only six jurors present. A grand jury will consist of 12 to 23 jurors. A petit jury can have as few as six jurors.
When Perry visits George Ballard, Ballard is listening to a radio show featuring folksy sportscaster "Red Walsh"-inspired by real life sportscaster Red Barber. Walsh predicts "the Beavers are a cinch to do it again this year". In 1957 the Oregon State Beavers did in fact repeat as Pacific Coast Conference football champions.