When Shelby is walking down the steps, he turns on a small flashlight. The beam is too large to be from that flashlight. When he places the flashlight down, no beam reflects on his shirt. When Frank picks up the same flashlight, again there is no beam shining.
When Frank is getting dressed, he puts on his pants and appears to have put on only one boot. He then runs out the door wearing two boots. He actually puts on two boots. You can see him reach down below the table to pull up the other one. Presumably, he slipped his foot in and pulled it up quickly. But the appearance given on screen is that he definitely put on two boots.
When Perry gets the telegram supposedly from Frank Lawton, Della recalls that Lawton was a lieutenant in Perry's company during the war, and Perry mentions that something happened to Lawton on D-Day. Both indicate that Perry and Lawton were in the Army. But in several later episodes in the series, such as The Case of the Travelling Treasure (1961), Perry is described as a Navy veteran.
The crew of a ship is also referred to as the ship's company. Therefore, if Lawton was on Perry's ship, he was in Perry's company.
The crew of a ship is also referred to as the ship's company. Therefore, if Lawton was on Perry's ship, he was in Perry's company.
Art Williams photographed a murder scene from a small boat. The camera angle shows the picture to have been taken from the shore.
An establishing shot of the Shelby house, supposedly taken late at night, was obviously taken in the daytime.
The transition shot after Perry and Paul visit the lakeside picnic area but before the interior court scene is a stock street scene with vehicles traveling by. All of the vehicles shown are 1940s vintage models without any contemporary mid-1950s models as would have dominated society at the time.
When questioning Mrs. Williams, the prosecutor refers to her as Mrs. Shelby.
Paul took a photo of the picnic grounds at around 1:00 p.m. Yet the shadows shown in the photo, which were a main part of case, are long, like they were cast at around 9:00 a.m.
The so-called infrared photograph shown near the end of the story, is not an infrared photograph. It is a standard photograph. Infrared photographs in the 1950's were hazy and distorted.
Police suspect that Scott Shelby was driven away from a lake by Ellen Waring, after having been shown by Perry Mason that the passenger seat of Waring's car was wet and that a man's wet clothes and shoes were in her garage. Soon after, it is established that Shelby has been dead for hours and cannot have ridden home with Waring. Neither Perry nor the police pursue the matter of how the car seat got wet or whose clothes and shoes were in the garage.