the 12 jurors and 12 alternates were chosen on tuesday after a selection process that began on january 20 .
experts say the jury selection in centennial , coloradp was among the largest and most complicated in u.s. history .
holmes is charged with shooting dead 12 people and wounding 70 others in the july 2012 attack at a movie theater in aurora .
his attorneys do n't dispute that he pulled the trigger but say he was in the grips of a psychotic episode when he opened fire .
among the 19 women and 5 men chosen , are a schools employee , a person with depression and a businesswoman who cares for her elderly parents .