Part 1: MARK THE FATHER OF 3 SONS

Jason, Owen, and Tyler are three brothers with a very strict father Jason is the oldest of the boys at age 15. Owen is 13 and Tyler is the baby at age 10. He is also a lot more naive and innocent than Jason and Owen. Their father Mark is super strict and there is always a punishment for bad behavior.
When Mark finds evidence that one of the boys has been smoking, something he strictly forbids, he expects the guilty boy to own up. If he doesn't then all 3 boys will be punished. Which one is the guilty one? Will he own up or will all three get punished? And what punishment is Mark planning to dish out?