Harry Hoo's name is spelled "Hoo" in the title but is spelled "Who" in the end credits.
The Chief berates Max for trying to apprehend the KAOS agent he was assigned to follow, saying he should never have drawn his gun on the man. However, there was no way for Max to avoid the gunfight, as he clearly returned fire in self defense (and in defense of the many bystanders) after the KAOS agent fired at him.
The Chief's thickly-framed wall map falls to the ground, dislodging all of the markers, when Max removes a single pushpin. However, a single pushpin couldn't possibly hold up a heavy coarkboard map, and most if not all of the pushpins should have remained securely seated in the cork backing even when dropped.
When Max and Harry Hoo are discussing the possibility of multiple murderers raised by the two cigarettes in the ash tray, they go back and forth suggesting an increasingly improbable number of non-smokers plus "only two smokers". They fail to consider the possibility of a smoker who simply opted not to smoke while murdering.
Max tells 99 that Harry Hoo went home to change because Max tore his coat. However, Max did not tear the coat, he stabbed a hole in it (and in Harry Hoo's back) during an overzealous reenactment of the murder they were investigating.
When 99 enters the hotel room where Harry and Max are surveying the crime scene, the shadow of the boom mic is clearly visible as the camera pans over.