Skip to Content

How does the Supreme Court decide cases?

The Supreme Court is the highest court in the United States. It has the final say on matters of constitutional law and interprets laws passed by Congress. But how exactly does the Supreme Court go about deciding cases and issuing rulings? There is a defined process that guides the Court’s deliberations.

The Supreme Court’s main role is to act as the final arbiter of legal disputes, ensuring that laws adhere to the Constitution. The Court hears cases that have made their way up through the lower courts and represent significant constitutional issues. When the Supreme Court agrees to take on a case, the justices examine the legal arguments from both sides and vote on the outcome.

While the Supreme Court tends to garner attention for its landmark rulings, the vast majority of cases it hears involve more mundane matters of interpreting federal and state laws and regulations. However, in all cases, the Supreme Court aims to offer the final word on what the law means. Its rulings set precedents that guide future court decisions at all levels.

How do cases reach the Supreme Court?

For a case to wind up before the Supreme Court, several things have to happen. First, an actual legal dispute with two or more sides must arise. One party claims that the other has violated the law in some way, leading to a lawsuit or criminal charges. The case must work its way through the lower courts. Either party can then appeal the lower court’s decision to a higher court. Most cases will not go any further than a state supreme court or federal appeals court.

But for cases involving substantial constitutional issues, one side may appeal again to the U.S. Supreme Court. Every year, the Supreme Court receives around 7,000-8,000 petitions asking it to hear cases. The Court usually agrees to hear arguments in only about 100-150 cases per year. The justices themselves decide which cases they will take on, reviewing petitions and voting on whether a case has sufficient importance. The Supreme Court tends to focus on cases that have divided lower courts or that address unclear constitutional questions. Cases that the Court declines to hear remain decided according to the last lower court ruling.

Who are the justices?

There are nine Supreme Court justices—one Chief Justice and eight Associate Justices. The Constitution does not stipulate any particular qualifications for justices, though most appointed have experience as judges, lawyers, or politicians. Justices hold office for life, until they resign, pass away, or are impeached and removed by Congress.

The President of the United States nominates justices when vacancies arise, typically due to retirements. However, the President’s nomination must be confirmed by the Senate. Since the 1970s, the process of nominating and confirming justices has grown increasingly contentious. Today, most nominees reflect the political leanings of the President who nominated them. Currently, six justices are considered to lean conservative, while three lean liberal.

How do the justices prepare for and hear cases?

The Supreme Court begins its annual session on the first Monday of October and continues hearing cases until late June or early July. In advance of oral arguments, the justices spend substantial time reading extensive written briefs prepared by the parties in the case. Each side submits a main brief explaining the facts of the case, relevant laws, and their legal argument. The justices and their law clerks carefully review these briefs and may request more information or clarification on certain points. Occasionally, the Court will handle a case based solely on submitted briefs, without oral arguments.

During oral arguments, each side has 30 minutes to present arguments, though justices often interrupt with questions. The two sides’ lawyers take turns fielding queries from the justices seeking to further probe the strengths and weaknesses of each legal position. The justices see oral arguments as an opportunity to gather any additional information they need to make a ruling.

How do the justices confer and issue decisions?

After oral arguments, the nine justices meet in a private conference to discuss each case and cast preliminary votes. The Chief Justice begins the discussion, with each justice speaking in order of seniority. After indicating how they plan to vote, the justices take an initial tally. If the Chief Justice is in the majority, he decides who will write the Court’s opinion. If not, that responsibility goes to the most senior justice in the majority.

Draft opinions are circulated among the justices. Members of the majority may write concurring opinions that agree with the outcome but differ on the legal rationale. Dissenting justices in the minority will also draft opinions explaining their disagreements. Through this process of sharing drafts, justices may shift their positions, leading to changes in the vote breakdown.

Cases must be decided before the Court’s term ends in late June or early July. While the Court aims for unanimity when possible, that is rare in highly controversial cases. The official decision announcing the Court’s ruling, including majority and minority opinions, is called the Court’s opinion. Justices may read summarized opinions from the bench, but the full written opinions are generally released several days or weeks later.

Who writes the opinions?

The justice assigned to write the majority opinion has significant influence, though the end result reflects input from other justices. The opinion needs to achieve consensus within the majority while persuading no one else to defect. For cases with fragmented votes and concurrences, the opinion may aim for relatively narrow conclusions, even if the author would prefer broader rulings. Dissenting justices use their opinions to point out flaws or express misgivings about the implications of the majority ruling.

Certain justices are renowned for their memorable writing or strongly articulated positions. But most opinions from the Court aim first forlogic and precision, not rhetorical flair. The Court’s legitimacy rests on presenting its decisions as grounded in established legal doctrine rather than ideological leanings. Still, the distinct philosophies and priorities of individual justices often emerge in how they interpret laws.

What happens after a ruling?

Once decided, a case is binding on lower courts and sets a legal precedent. The Court may agree to hear follow-up cases if new legal issues arise in implementing the original ruling. On very rare occasions, the Court has outright reversed precedent established by an earlier ruling. More often, later decisions limit, expand upon, or distinguish earlier rulings. The Court may refrain from delving back into issues it sees as sufficiently settled by past cases. Thus, its rulings collectively build an evolving body of jurisprudence.

Beyond judges and lawyers, Supreme Court rulings often substantially impact the lives of everyday Americans. Landmark cases define and redefine policies on topics like civil rights, freedom of speech, police powers, voting methods, and more. While the Court aims to stand apart from shifting political opinions, in practice its members’ philosophies shape their interpretations, leading its jurisprudence to lean conservative or progressive at times. Americans often react strongly for or against the Court’s decisions, sparking debates about responses ranging from new legislation to constitutional amendments. Thus, the effects of the Court’s rulings reverberate far beyond its marble halls.


The Supreme Court wields enormous power yet works hard to seclude itself from day-to-day politics and maintain its lofty position in American civic life. How the justices deliberate and decide cases reflects this tension. Their processes aim to ensure rigorous, independent legal analysis while acknowledging that judges have worldviews. The lifetime appointments shield the Court from elections and campaigns but resistance to modernization also raises concerns. Procedural traditions and exhaustive work behind closed doors promote caution and consensus—yet controversial cases still incite 5-4 votes along ideological lines. The Supreme Court’s defining role may be its studied pace in serving as the final arbiter of American law.