Lewis had accused him of sleeping with his girlfriend and, although he had denied the accusation, Lewis had insisted on starting a fight.
Smith said Lewis had tried to take his hoodie from him and rob him of anything he had in his pockets in lieu of a fight. He said he had walked away from the confrontation a number of times but Lewis and another youth prevented him from walking home.
Smith said Lewis pushed him and abused him before trying to forcibly take his hoodie off him. Finally Smith said he pulled the knife out of his pocket and swung it around and into Lewis' back three times. Injuries included both lungs being penetrated and the aorta being partially severed.
Lewis had run a few metres from the scene but collapsed and died from blood loss a few minutes later.
Smith said it was several hours before he discovered the stabbing had been fatal. He said he had then run away from the scene and had thrown away the knife.