Corrections

The Suprem Court has a very important role in US constitutional system of government.

As the highest court in the each land, it's the court of last resort for those looking for justice.

Moreover, due to its power of judicial review, it plays an essential role in trying to ensure that branch of government recognizes the limits of its own power.

Finally, it protects civil rights and liberties, upholds the rights of citizens like freedom of speech, freedom of religion...

This court can declare presidential acts and laws unconstitutional.

It is the final judge in all cases involving laws of Congress and the highest law of all : the Constitution.

It can tell Congress if a law it passed violated or no the U.S Constitution.

Article 3 of this one establishes the federal judiciary : “The judicial Power of the United States shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish”.