In an effort to combat drunk driving, a checkpoint is established where every fifth car is stopped. As Deft is approaching the checkpoint, he pulls over to the side of the road a block before the checkpoint, turns his car around, and proceeds away from the checkpoint. Officer notices this and pursues Deft. Shortly thereafter, Deft is stopped by Officer. When Officer approaches Deft's car, Deft immediately explains that the reason he turned around was because he is in a hurry and didn't want to be detained at a checkpoint. Officer believes Deft. However, she asks Deft to exit the car and she then pats him down for weapons. Finding no weapons, Officer tells Deft to return to his car. However, Deft seems to be having difficulty fastening his seat belt. Officer asks him what the problem is, and Deft replies, "Okay, you caught me. I smoked a little marijuana." Hearing this, Officer takes Deft into custody, reads his Miranda Rights, and when Deft is asked if he understands, Deft replies, "How can I understand anything when I told you I was high?" At the police station, Deft is taken into an interrogation room where he signs a confession indicating that he used marijuana that day, and that he was driving under the influence of it. You are Deft's attorney. What issues will you need to consider before his trial?