Marbury vs. Madison was a critical Supreme Court ruling in 1803 that established the notion of "judicial review" in the US by, for the first time ever, declaring an act of Congress to be unconstitutional. Chief Justice John Marshall, writing an opinion for the majority, essentially forced the Republican Jefferson administration to follow the letter of the law and officially commission Federalist judge William Marbury, who prior president John Adams had appointed to a judgeship before leaving office.
In this way, the principle of judicial review—in other words, a court's ability to strike down, modify, change, or legitimize laws created by Congress when evaluated according to a preexisting doctrine (like the US Constitution)—became a radical leap in power for the judicial branch, solidifying its status as a co-equal branch of government and as the ultimate arbiter of constitutional law.
However, such a decision did not end the debate over the judiciary's authority. In fact, it has...
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