Question. Context: Since the Supreme Court was established in 1789, 17 persons have served as chief justice. The first was John Jay (1789 -- 1795). The current chief justice is John Roberts (since 2005). Four -- Edward Douglass White, Charles Evans Hughes, Harlan Fiske Stone, and William Rehnquist -- were previously confirmed for associate justice and subsequently confirmed for chief justice separately.

Question: who is the chief justice of the united states supreme court?
Answer. John Roberts
What step-by-step reasoning justifies that answer?
Reasoning: The relevant sentence in the passage is: The current chief justice is John Roberts (since 2005).