The former nurse's defense says she was in the grip of bipolar disorder and postpartum psychosis

Lindsay Clancy's legal team does not deny that the Massachusetts mother killed her children, but is arguing she shouldn't be held criminally responsible because she was mentally…

Lindsay Clancy, 36, is on trial for killing her three children, Cora, five, Dawson, three, and eight-month-old Callan, at her Massachusetts home.