Gideon v. Wainwright [somewhat] famously incorporated the 6th Amendment's guarantee of representation even to those who cannot afford it (so-called indigent ("poor") counsel).  There's also a movie about this case called "Gideon's Trumpets." 

The answer, "the right to be represented by the best . . ." may sound tempting, but it is not true. The state must provide you with counsel if you cannot afford it (if you want it, that is), but there's no requirement that your representation be the best.

The other answers are different Amendments that were not relevant to the case.

Brown v. Board is the correct answer. It was in this case that Chief Justice Warren declared unconstitutional segregation in public education. The language “with all deliberate speed” became nearly as famous as the case itself.

One precautionary note before continuing to the incorrect answers: technically speaking, there are TWO Brown v. Board cases—the first in 1954 (Brown I) the second in 1955 (Brown II). Brown I is the case that says segregation in public schools is unconstitutional. Brown II answers the question of “how fast should we remedy this problem” with “with all deliberate speed.” This is a hyper-technical distinction, but a relevant one nonetheless.

Although Plessy v. Ferguson may sound correct (hopefully it sounds familiar), it is not the correct answer. Brown v. Board actually overturns (that is, says it is incorrect) Plessy. More specifically, Plessy held that, so long as segregation was “separate but equal,” it was OK—that is constitutional. Brown directly contradicts that, saying “The ‘separate but equal’ doctrine adopted in Plessy v. Ferguson has no place in the field of public education.”

Gibbons is incorrect as it is a case dealing with Congress’ ability to regulate commerce.

Citizens United is incorrect as it is a case dealing with the interplay between the First Amendment and election contributions.

Ex parte Milligan is a case dealing with the suspension of habeas corpus during the Civil War.

Gibbons v. Ogden is the correct answer. To begin with, you should be able to eliminate one contender from the list: Brown v. Board of Education. Not only is Brown arguably the most famous case on that list, it is also the youngest (relatively speaking). Remember: the Supreme Court decided Brown in 1954! More importantly, Brown had nothing to do with the regulation of interstate commerce—Brown declared unconstitutional segregation in public schools.

Next, you should eliminate Plessy. The Supreme Court decided Plessy in 1896, long after Chief Justice Marshall’s tenure on the Supreme Court (and life, for that matter) was up. Moreover, Plessy—similar to Brown—dealt with race relations, rather than directly addressing interstate commerce. In fact, Plessy is the Supreme Court case which rather famously held “separate but equal” accommodations to be constitutional. Remember: Brown overruled Plessy!

Finally, we come down to the three cases all decided by the Marshall Court. (Remember: particular eras in the Supreme Court are referred to by the name of the presiding Chief Justice; thus, any case decided between 1830-1834 we would refer to as decided by the “Marshall Court” as Chief Justice Marshall presided during that time). Out of the three remaining, Barron v. Baltimore may be a tempting answer. But, remember that Gibbons had to do with a squabble started by the New York legislature. Because, somewhat obviously, Baltimore is not New York, the name of the case itself should give you a hint in the right direction. More importantly, however, Barron revolved around 5th Amendment issues—eminent domain, in particular (do you remember what ‘eminent domain’ means?).

That leaves only Gibbons and Marbury as the remaining answers. Marbury may be a tempting choice—it is arguably one of Marshall’s most famous (and probably confusing) cases, but it is not about interstate commerce! Marbury centers on the difference between “original” and “appellate” jurisdiction (do you remember the difference?).

Thus we are left with Gibbons, the one and only correct answer. The background of Gibbons is relatively interesting: in brief, it is about a state-chartered (a fancy term for “granted”) monopoly which ended up implicating the financial interests of Mr. Gibbons. More specifically, Gibbons had to pay an exorbitant sum to operate his steamboat ferry (which, importantly, ran from New Jersey to New York) in the waters of New York (because the legislature gave a monopoly to Ogden). Understandably, Gibbons was rather . . . steamed . . .  about this, hence this case. The short of it is that Gibbons won, because New York overstepped its authority by issuing such a monopoly; the Constitution gives the power to regulate “interstate commerce” (that is business—whether it be actual goods or people—in between states) to Congress. Because Gibbons ran a ferry in between New Jersey and New York, New York’s prohibitions implicated interstate commerce.

Full disclosure: this is an incredibly difficult question. For one thing, many law students don’t understand what actually happened in Marbury v. Madison—it’s a VERY complicated case. For another, there are words like “jurisprudence” and “habeas corpus” that sound very official and legal (they are!) but are no doubt confusing. Thus, if you got the answer correct, give yourself a pat on the back. Great job! If you didn’t, don’t worry; (hopefully) everything will make sense by the end of this.

To begin with, you have one major hint to help you eliminate answers—the inclusion of the authoring Justice. In plain English, every answer is preceded by “Chief Justice [NAME].” This is huge! If you can remember the court era, you can parse down the answers to two choices—both answers beginning with “Chief Justice John Marshall.”

Before going into that rather detailed explanation, however, let’s briefly discuss why the other answers are all incorrect. To begin with, the one beginning "Justice Scalia" can’t be right. First, he is a current Supreme Court Justice and, contrary to popular belief, he is not 200 years old. Second, unless you’re a bankruptcy law guru, you should have no idea what §506(a) and “cram down” are. These are what we call “red herrings”—false leads.

The next two wrong answers must be those beginning “Chief Justice Roger B. Taney.” The one involving habeas corpus is a real case, albeit massively oversimplified, but wrong for two reasons: (1) Taney didn’t write that opinion (hard to write when you’re dead), Salmon P. Chase did; and (2) Marbury has nothing to do with the suspension of habeas corpus. The answer involving African Americans is also a real case, written by Taney, nonetheless, but over the wrong subject matter! (Question: Do you remember the case name?)

This leaves us with the two answers beginning “Chief Justice John Marshall.” The one involving the Federalists is wrong for several reasons. To begin with, Marshall was likely sympathetic to the Federalist cause, having been appointed by a Federalist president (do you remember who?) and confirmed by an overwhelmingly Federalist Congress. Moreover, the underlying suit was not about removing Marbury from his post as Justice of the Peace, but about Marbury being allowed to become a Justice of the Peace.

Now, the reason for the correct answer!  Remember that Marbury was appointed as Justice of the Peace by outgoing president John Adams. To make a very complicated matter short(er) and less complicated, there was a hiccup with Marbury’s “commission”—that is, essentially, the piece of paper that allowed him to begin working as Justice of the Peace. In order to resolve this hiccup, Marbury did the very American thing and sued. Specifically, he sought a writ of mandamus, which is a court order compelling an official to do something. If you guessed that he wanted the official, Madison in this case, to hand over his commission, you are correct. Chief Justice Marshall more or less expressed his sympathies for Marbury’s plight, but said he could not issue the writ of mandamus because the statute (the Judiciary Act of 1789) on which Marbury relied for jurisdiction*  was UNCONSTITUTIONAL. This case, then, is the first articulation of the Supreme Court’s power of Judicial Review. Remember: Judicial Review means the Supreme Court ([now] comprised of 9 unelected men and women) can declare that a law, passed by [at least] a majority of both chambers of Congress and signed into law by the somewhat-publicly elected President is void! By doing so, Marshall reminded America that the Supreme Court was a force to be reckoned with—that although they did not control the armies or the treasury as the President and Congress do, they had just as much power as the other two branches.

* Jurisdiction essentially means that a particular court is allowed to hear your case; because courts are of limited jurisdiction, they can only hear certain cases (please be aware this is a massive oversimplification). Take, for example, a court that deals with eviction proceedings—do you think that court has the jurisdiction to hear a case involving petty theft?

No tricks on this question—more rote memorization. Mapp v. Ohio is the correct answer. The facts of the case are actually pretty interesting and I encourage you to look them up (teaser: it involves a fake search warrant and the Ms. Mapp shoving the “search warrant” down her dress). At any rate, Chief Justice Earl Warren wrote the majority opinion incorporating the Fourth Amendment right to be free from unreasonable search and seizure.

The others are all incorrect. Escobedo v. Illinois involved the right to counsel during interrogations; Miranda v. Arizona involved the right to be told you have a right to counsel; Giddeon v. Wainright incorporated the right to indigent counsel; and Miller v. United States is a rather obscure case touching on the Second Amendment.

Scott v. Sanford was the case of whether a slave (Scott) was considered free if the slave was taken to a free state and then brought back into a slave state. The Supreme Court declared that it actually couldn’t hear the case because Scott was not a citizen, since he was black and the descendant of slaves, even though he was born in the United States. This outraged many abolitionists and is considered the worst decision in the history of the court by many scholars. There was never an official court case that overturned this case, but the 14^th Amendment is considered to have essentially overturned it. The 14^th Amendment made it so that anyone born in the United States is a citizen. Its immediate effect was to grant citizenship to all former slaves, as the Amendment was added right after the Civil War.

The police admitted that the search was illegal in this instance, even though they discovered obscene materials and charged Mapp with a crime. The appellant, Mapp, argued to the Supreme Court that it was a situation where expressing herself in her own privacy was protected by the 1^st Amendment, but the Court ruled in her favor through the 4^th Amendment. The 4^th Amendment protects against unlawful search and seizure, and bestows the right of security in one’s home. The exclusionary rule allows for much evidence to be ruled inadmissible as evidence in court.

The Supreme Court ruled that so long as there were separate facilities for both black and white people and both facilities were kept in equal condition, then segregation was legal. The Court argued that the equal protection clause in the 14^th Amendment was not violated so long as the separate facilities were equal. This case held precedent until the Brown v. Board of Education decision in 1954, when separate-but-equal became legally arbitrary.

In 1919, the Supreme Court ruled that these situations should be taken on a case by case basis, due to the uniqueness of each emergency situation and the character involved. In this instance, they found Schenck to be a danger to the military by creating dissension amongst the ranks and potential draftees with his peaceful pamphlet distribution. The clear and present danger test was used by the Court as a measuring stick of the detriment Schenck committed and whether or not his actions would create problems that could be remedied by the Court’s decision.

This case is so important because of the definitive line drawn between states’ rights and federal rights. Chief Justice John Marshall explicated that the commerce clause established Congress as the penultimate adjudicator of interstate commerce, and state laws take stride from Congress’ lead in all such matters.