Checks and balances supreme court is granted power to overturn congressional laws that violate constitution. the courts however should exercise judicial constrain while doing that, to ensure the do not injure the principle of separation of power. usually they all restrain themselves to comparing whether the new law contradict the establishment clauses which would require a referendum, or the wording and legal process was followed. This ensures congress is checked.
I don't know try looking in your book. I'm a college teacher that knows this site is cheating and I will tell your teacher this and you will get expelled
