I do not understand why oral and written can both be defended in court. I assumed since a written agreement is a piece of paper and has signatures meaning that the terms written above are agreed with there is really no way to dispute it. Whereas with oral agreements someone just has to say they did not agree with it and then there is really no way to prove that they did unless the conversation was recorded. With oral agreements its all by word of mouth and they can easily be changed at any moment where as the written agreements are copied and saved so changing them will be very difficult.