After 20 years in jail, Kathleen Folbigg has been pardoned. Ms Folbigg was found guilty of killing three of her young children and for the manslaughter of her fourth between 1989 and 1999.

However, two decades later, new scientific evidence was found to cast reasonable doubt on her conviction.

To explain what new evidence was brought forward, and what it meant for the case, John Stanley was joined by COSMOS Magazine journalist Matthew Ward Agius.