The Case of the Wayward Wife - S3-E13
Factual error: May buys a book for 4.95. Give the clerk a $10 bill but the register shows change of $5.15.
Perry Mason (1957)
1 factual error in season 3
Starring: Raymond Burr, Barbara Hale, Ray Collins, William Hopper
The Case of the Sausalito Sunrise - S9-E19
Other mistake: The owner of a Los Angeles trucking company tells a driver who is going to San Francisco, "Take the San Diego Freeway toward Bakersfield." That freeway runs from San Diego to San Fernando. It does not go toward Bakersfield.
Hamilton Burger: Incompetent, irrelevant, and immaterial.