The Supreme Court didn't have its own building until 1935. Until then, the highest court in the land was held in various sites around DC, including a tavern. The Supreme Court is in session from the first Monday in October until the docket is cleared in late June. October through April, visitors can hear the oral arguments presented to the court, or see the judgements handed down in May and June. There is also a free film and displays explaining the court proceedings on the ground floor.
Visitors can view the court at work by waiting on either of two lines.
One line will allow you to get a quick glimpse at court proceedings, while another in-depth excursion is available.