With President Donald Trump and first lady Melania Trump watching, Justice Neil Gorsuch on Thursday was officially invested as the 101st associate justice of the United States in a brief, formal ceremony in the U.S. Supreme Court.

As the ceremony got underway, Gorsuch sat in the well of the courtroom in the same chair used by Chief Justice John Marshall during the early 19th century and used for the investiture of every member of the court since Lewis Powell Jr. took his judicial oath in 1972.

After the clerk of the court read the presidential commission appointing Gorsuch, the new justice walked up to the bench where Chief Justice John Roberts Jr. administered the oath. Gorsuch thanked his colleagues for their “warm welcome.”

Former Republican attorneys general Edwin Meese, Alberto Gonzales, John Ashcroft and Michael Mukasey attended the ceremony along with a number of Republican U.S. senators, including Senate Majority Leader Mitch McConnell of Kentucky, Orrin Hatch of Utah, and Ted Cruz of Texas.

Other attendees included White House counsel Donald McGahn, former U.S. Solicitor General Kenneth Starr, and veteran Supreme Court advocate David Frederick of Kellogg, Hansen, Todd, Figel and Frederick, the firm in which Gorsuch practiced earlier in his career.

Trump’s pick for solicitor general, Noel Francisco, also attended the event, as did Latham & Watkins partner Gregory Garre, a former U.S. solicitor general.

The judicial oath is one of two oaths taken by the justices. Gorsuch took the constitutional oath in a private ceremony April 10 at the Supreme Court. Later that day, Justice Anthony Kennedy administered the judicial oath in a Rose Garden ceremony.

Justices Sonia Sotomayor and Elena Kagan took their oaths in a private ceremony at the court with a video feed. They later had an official investiture ceremony in the courtroom.