successfully by use contributory negligence, volenti non fit injuria and damnum fatale to escape liability.
In the case (b), the defender is the bus driver, he had out of control of his vehicle when the accident happened, so the bus collided head on with Margaret s car. It is unexpected. At the same time, Margaret was not wearing her seat belt at the time of the collision, it is Margaret s negligence. So the defender coule use contributory negligence to escape liability successfully.
In the case (c), the Knockbuckle players, lost his temper and kicked Gavin in the face during a scrum and he makes a excuse for this called that accidents will happen and anyone who plays the game knows this. It is an intentional act, he wants to use immunity to escape his liability. I think It is chicanery and it never would have succeed.