The Supreme Court of Appeal in South Africa will hear the National Prosecuting Authority's appeal against the six-year sentence handed down to the athlete, Oscar Pistorius, in November.
It's the second time the state has contested verdicts over the killing of Pistorius's girlfriend, Reeva Steenkamp, in 2013.
They successfully overturned the initial verdict of culpable homicide.
Now they will argue that Pistorius should have received the prescribed minimum of 15 years for the killing.