Monday was day three in the murder trial of Paris Illinois teen Terry Payton.
He is accused stabbing his mother, Kathie Payton, to death in June 2011.
The defense says it was all in self defense.
Witnesses testified to the tense relationship between mother and son.
Several said that the two would argue and scream and that the mother would sometimes lock Terry out of the house.
The trial is expected to take the rest of the week.