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 ill — in the grip of bipolar disorder and postpartum psychosis. Prosecutors say she plotted to get her husband out of the house so she could carry out the murders.

Jurors hear from host of medical experts as defence says postpartum psychosis caused young mother to kill children

A defense lawyer for the Massachusetts mother who killed her three young children is questioning her psychiatrist's expertise, prescribing decisions and overall treatment.