The Supreme Court will fast-track a major case challenging President Donald Trump’s tariffs on imported goods, a key policy of his second term. The legal question is whether Trump has the authority to impose tariffs on his own, without Congressional approval, under the International Emergency Economic Powers Act, a law intended for emergency situations.

The court consolidated two related cases. One was filed by the Trump administration after the U.S. Court of Appeals for the Federal Circuit ruled on Aug. 29 that the president exceeded his authority. The second case was brought by two educational toy companies, Learning Resources and hand2mind, challenging the legality of the tariffs.

For the time being, the tariffs remain in effect while the Supreme Court examines the cases. Oral arguments are scheduled for the first week of November, with a ruling expected to follow later.

The lawsuits target two specific sets of tariffs. The first is reciprocal tariffs, which vary from 34% for China to a 10% baseline for other countries. The second is a 25% tariff imposed on certain goods from Canada, China, and Mexico, aimed at pressuring these nations to reduce the flow of fentanyl into the U.S. Tariffs imposed under different legal authorities, such as 50% duties on steel and aluminum, are not part of the Supreme Court review.

Even if the court rules against Trump, the administration could still pursue other tariff measures using alternative legal tools.

Several businesses and states have challenged the tariffs. Five companies requested that the Supreme Court step in immediately due to the high stakes, while a group of 12 states also filed suits to block the measures. In the second case, the educational toy companies had previously asked for an expedited review earlier this year.

The Supreme Court’s decision will have major implications for the limits of presidential authority over trade and could affect how future administrations implement tariffs without congressional approval.