Chief Justice John Roberts stressed the importance of judicial independence during public remarks Wednesday, noting that the judiciary’s role as a co-equal branch of government is central to the nation’s political system.

“The judiciary is a coequal branch of government, separate from the others with the authority to interpret the Constitution as law, and strike down, obviously, acts of Congress or acts of the president,” Roberts said at an event in his native Buffalo, New York.

The judiciary’s role, Roberts added, is to “decide cases but, in the course of that, check the excesses of Congress or the executive.”

That work, Roberts said, “does require a degree of independence.”