part of the lesson he taught was practical defense law with a special focus on florida laws like stand your ground and zimmerman aced the class. >> he was probably one of the better students in the class. >> reporter: zimmerman's defense team argued his past training and education had no relevance to this case. next, prosecutors called amy siewert, a firearms expert with te florida darmt epartment of l enforceme enforcement. she said she was able to determine it was a contact shot that killed him. >> it was consistent with the firearm touching the outer sweatshirt and inner sweatshirt being in direct contact with the outer one, yes. >> reporter: the final witness, anthony gorgone, a crime lab analyst who examined dna evidence in this case and questioned whose dna was found on zimmerman's gun. >> you were able to exclude