When they are pulling up to the stop sign in the encounter with the drunk driver, Reed's window alternates between open and closed between camera shots. The same thing happens when they pull up on the con artist's truck.
Following the butane tank explosion, Malloy grabs the man and Miss Sorenson and leads them behind the police car. From the long shot, there is a car approaching. Cutting to a close up in the next shot, that car is no longer seen.
Winnie Goodrich chastises her drunk husband, Ira Goodrich, for not stopping at the stop sign. At that intersection, it is shown in the shot before that the perpendicular direction to the Goodriches that Malloy and Reed are traveling in has the stop sign in both directions, but that the direction the Goodriches are travelling has the right-of-way i.e. no stop sign.
Typical procedure policy for a department as large as LAPD would be for Reed and Malloy establish a perimeter, thus containing the two burglars, and call for back-up on their portable radios. However, while most police departments had portable units based on military radios by 1960, early models weighed approximately 5 pounds. Later models were lighter but still the size of a brick so may not have been easily carried.
Mrs. Merchant says that the taller of the two Johnsons is taller than either Malloy or Reed, and the shorter one is about their height. Later, as Reed and Clyde Johnson, the taller of the two Johnsons, are standing side-by-side as Reed has him in handcuffs, they are approximating the same height (it is difficult to gauge with Reed wearing his cap), but as Malloy and Arver Johnson stand side-by-side as Malloy hauls Arver out of the truck, Arver is significantly shorter than Malloy or Reed.
Upon entering the house with her, Malloy asks Emma if they - as in the Johnsons - are in the basement, she responding affirmatively. There is no way she could have known for sure they were in the basement, with at least Arver Johnson having been on the main floor when Emma was out of the house with Malloy.