Roth was the Court's first major review of obscenity law. It's decision upheld the view that obscene materials were not protected by the First Amendment, while mandating a clearer definition of what is obscene. As such, it broke prohibitions against obscenity away from the common law of centuries past, and introduced it to judicial management and interest group pressure.

Laws against the sale, display and possession of obscene materials first appeared in the United States in the early nineteenth century. At that time, and for the subsequent century and a half, the notion that obscenity might be difficult to define was not entertained to any great degree by either the people or the courts. The Supreme Court made only passing references to the constitutionality of the restrictions in a handful of cases, always finding them outside the purview of the First Amendment. During this period, even works of seeming literary value, but which were inherently obscene, were restricted.

In Roth, and a companion case, Alberts v. California, the Court continued to uphold the historical and precedential view that obscenity was not protected by Freedom of Speech, finding that it was the equivalent of conduct, not speech.

However, the Court went further in the case and said that, unlike in the past, the test for obscenity would have to meet the requirements of the First Amendment, which protects all speech, regardless how unpopular, that attempts to convey ideas.

The traditional American test for obscenity had mirrored an 1868 English case, Regina v. Hicklin, which found materials obscene when any part of them tended to "deprave and corrupt" the most susceptible in the audience. The Roth Court rejected this test, but did not specifically replace it. It stated only that henceforth, materials could be deemed to be obscene only if they appealed to the "prurient interest [of] the average person", when "taken as a whole".

In so stating, as the dissent reiterated, the Court substituted a far more vague test for the historical understanding that had survived the previous century. Arguments over the meaning of "taken" (which sounds like an argument over "is"), and "whole", as well as concerns over what constitutes the "average person", have simply led to new efforts to redefine obscenity.

Perhaps most pointedly, the Roth test's use of the "average person" removes the "most susceptible" attribute from the earlier traditional test. As such, obscene materials which can in some way be represented to convey an idea, are at least in theory available to children incapable of grasping anything beyond their obvious sexual connotations.

The Roth test was made moot in the 1973 case of Miller v. California, where Chief Justice Warren Burger created a new three-pronged test. The new standards, while offering some hope for communities to participate in the definition of obscenity, also allowed even more leeway for "social value". Unfortunately the practical effects of Miller, like Roth, were far more amenable to the spread, rather than the reduction, of public obscenity.