Your perspective can influence the speech because of your experiences.
Say that you had an experience on the topic, and you now have background evidence to support your side. The other side will contradict you but they may not know what it feels like to be in the experience of the topic.
Therefore, your perspective can make your speech biased, or it can be proved with evidence. This is all caused by your perspective on the topic.
In this case, the Supreme Court ruled that the constitution is the supreme law of the land and that the courts have the power of judicial review. Another principle established by John Marshall was that a loose view of the constitution is legal.
