Factual error: In the second case, Phoenix arrives on the scene of the crime just 11 minutes after the murder occurred, but examining the body, he finds the murder weapon "encrusted with dried blood." In that short of a timespan, the blood would be anything but crusty - especially considering that the smell of blood is so strong that Phoenix can feel it from the corridor.
Continuity mistake: During the first case, when Mr. Sawhit has the first of the series' patented witness breakdowns, he angrily tosses his toupee at Phoenix. However, in the courtroom shot from behind, he still has a full head of hair.