Facts of Marbury v. Madison:
In the weeks after John Adams lost his bid for reelection to Thomas Jefferson in 1800, the Federalist Congress increased the number of circuit courts. Adams placed Federalist judges in these new positions. Since several of these 'Midnight' appointments were not delivered before Jefferson took office, he immediately stopped their delivery. One of the justices of the peace, William Marbury, filed a writ of mandamus demanding Secretary of State James Madison deliver the appointments. The Supreme Court led by John Marshall denied the request citing part of the Judiciary Act of 1789 as unconstitutional.
Significance of Marbury v. Madison:
This historic court case established the concept of Judicial Review or the ability of the Judiciary Branch to declare a law unconstitutional. This case brought the Judicial Branch of the government on a more even power basis with the Legislative and Executive Branches. The Founding Fathers expected the branches of government to act as checks and balances on each other. The historic court case Marbury v. Madison accomplished this end thereby setting the precedent for numerous historic decisions in the future.