Goofs

The district attorney introduces himself to Mason as Darwin Hale, but later in his office, Betsy Burris calls him Bill Hale.

The entrance to Perry's lodge is upstairs and completely covered by trees so it is shaded, but looking out the door when Della enters a few sparse trees are showing along with sky and sunlight.

A lone fingerprint lifted from a door handle is supposedly a right thumbprint. It's difficult to tell a thumbprint from a fingerprint, and impossible to be sure whether it's from the left or right hand.

When Sam and Betsy are looking through the binoculars, the camera shows a single vision field, as if they were looking through a telescope. If both lenses are properly adjusted, the single vision field is the proper view.

In the courtroom with the camera facing Perry Mason at the defence table, Barbra Hale is not sitting at the table, when the editing had been done Barbera is sitting there.

When Betsy first begins to testify, you can see the shadow of one of the crew on her left shoulder (camera right). The scene shifts and moments later, the shadow is no longer there.

The nosy neighbors awoke due to the scream of a woman but nobody heard a gunshot which is much louder than a scream.

Della leaves the door to the lodge wide open when she enters, and no one closes it.

The victim's girlfriend tells Perry he is defending a murderer, and Perry simply says, "I am." This is an unforgivable statement from any defense attorney, and doubly so from the agile-witted Perry Mason.