A total of thirteen robberies are attributed to the two suspects, always committed by one or the other acting alone. However, the end narration indicates that each was convicted of eleven separate counts of robbery in the first degree.
Friday and Gannon follow a trail of blood spots to quickly find a suspect who escaped from the patrol officers. Real police officers would not have waited for detectives to pursue an active shooter, particularly one fleeing on foot and leaving a clear trail behind him.
As Gannon opens his sandwich in the break room, Friday gets a call that another robbery has occurred. The clock on the wall behind Gannon shows it is nearly 5:45 pm. In the next scene as the officers approach the site of the robbery, Friday narrates that the robbery happened at 6:25 pm.
A lineup is supposed to be as neutral and unbiased as possible. With the actual perp's cheek bandaged from his GSW, surely the other seven men in the lineup (here called a 'show up') would wear a similar bandage so that one of them will not stick out in the crowd the way that he does here.
The radio in the police station is the front panel of a Hallicrafters S20R. There is no cabinet containing the actual radio behind it.
At 11:31 pm (as indicated by Friday's narration), he tells Gannon he can go home. Gannon says, "good, I promised Eileen I'd help her oldest boy with her homework". By time Gannon got to Eileen's house it would be well after midnight. Too late for any young student to be doing homework.
When Gannon tells Friday that his son is studying advanced calculus, he clearly draws the shape of an equilateral triangle in the air. While calculus has many applications, it is fundamentally the study of continuous change, dealing with lines and curves rather than enclosed shapes. Triangles fall within the domain of trigonometry (the study of triangles) and geometry (the study of shapes). This is clear evidence for Friday's implication that Gannon doesn't know anything about calculus.