A recent car accident has Mac re-evaluating a case in which a driver went to jail for 18 months for hitting a cyclist because he was txt'ing while driving. Mac believes that despite the man's confession, he wasn't the driver and was protecting the person who was. The evidence was inconclusive (Mac's recent accident made him realize the bruising from the seat belt was on the wrong side for the man to be driving), but the confession made everyone stop paying attention to the evidence. Turns out Mac is right, but comes to understand the man's motivation.
Also, Lindsay gives birth to a baby girl.