(AP Photo/Andrew Harnik, File)

Newly sworn-in Justice Brett Kavanaugh took an active role on his first day on the Supreme Court bench.

FOX's Jared Halpern has more from Washington:

Chief Justice John Roberts welcomed Justice Kavanaugh to the court, wishing him a long and happy career. Kavanaugh's family watched arguments, so did retired Justice Anthony Kennedy.

Kavanaugh asked several questions about 20 minutes into the first hour of arguments; a case dealing with sentences for crimes considered violent.

Outside the court there were protests, along with more than a 100 people who lined up to watch arguments inside.

As the junior most Justice, Kavanaugh's duties include taking notes at a weekly closed-door conference and serving on the court's internal cafeteria committee.

In Washington, Jared Halpern, FOX News.

Follow Jared Halpern on Twitter: @JaredHalpern