The insanity defense sets up a two-part trial with differing burdens of proof. In the first phase, the state needs to prove Carpio is guilty of four charges beyond a reasonable doubt. Krause reminded potential jurors at the beginning of the trial that Carpio is presumed innocent and the state must prove otherwise.

In the second phase, Krause explained, the burden of proof shifts to the defense in its argument that Carpio cannot be held legally responsible for any of the alleged crimes.
By a preponderance of the evidence, the defense must be able to show that if Carpio killed Allen, Carpio did not appreciate the wrongfulness of his action because of mental disease or defect.

A preponderance of the evidence is a lesser standard than beyond a reasonable doubt. Robert L. Sheketoff, Carpio's lawyer, told potential jurors that the phrase means "more likely than not."

-- With reports from Journal staff writer Gregory Smith