BOSTON, US - A Boston-area woman was convicted on Tuesday of second-degree murder in the 2006 death of her 4-year-old daughter from an overdose of powerful psychotropic drugs.

The case rekindled a debate about the rising diagnosis of very young children with serious psychiatric conditions, and their treatment with potent medications.

A judge sentenced Carolyn Riley, 35, to life in prison with eligibility for parole in 15 years after a jury convicted her in Brockton, Massachusetts. She is expected to appeal.

Her husband Michael Riley, 37, will be put on trial separately starting in early March on murder charges in his daughter's death.

Prosecutors said Riley and her husband fabricated severe behavioural problems in their daughter to obtain drugs and to qualify for federal disability benefits, then overmedicated the girl to keep her quiet.

The defense attributed the death to rapid-onset pneumonia and said the parents were following a psychiatrist's direction in the cocktail of drugs given to the girl.

The jury deliberated for almost four days before returning the guilty verdict after a three-week trial.

Rebecca Riley was diagnosed with bipolar disorder, a condition characterized by severe mood swings, and attention deficit disorder before her third birthday, and placed on the medications at that time.

A state medical examiner concluded that Rebecca died of a combination of Clonidine, a blood pressure medication sometimes given to attention deficit hyperactivity disorder patients;

Depakote, an anti-seizure and mood-stabilizing drug used to treat bipolar disorder; and two over-the-counter drugs including a cold medicine. --REUTERS