CARROLL, Iowa (AP) – The defense has rested its case in the first-degree murder trial of a Minnesota man charged with killing a convenience store clerk in northern Iowa. Michael Swanson, of St. Louis Park, Minn., was 17 when he was charged with killing Sheila Myers on Nov. 15, 2010 in Humboldt – one of two store clerks he’s accused of killing that day.

The defense rested this morning during the trial in Carroll, after calling Swanson’s mother, Kathleen, as a witness on Wednesday. The state today called rebuttal witnesses, including a psychiatrist. Michael Taylor says Swanson understood his crimes, as well as right from wrong.

Taylor says Swanson told him the slayings were brewing inside his head since he was 13, and his original plan was to wait until he was 18 and kill his parents.