By Paige Long

Law360, London (April 21, 2020, 7:41 PM BST ) The U.K.'s Supreme Court swore in George Leggatt as its newest justice on Tuesday in a pared-down ceremony due to COVID-19 restrictions as the court gears up to hear high-profile cases including a challenge poised to shape the future of class actions.

Justice Leggatt, who has been a Court of Appeal judge for the past two years, replaced Justice Robert Carnwath, who retired on March 6, in a ceremony with only himself and the president of the top court. 

The Supreme Court building has been shut since March 24 in response to the government's social-distancing policy to combat the coronavirus pandemic, and all hearings have been conducted via video conferencing software, streamed to the public through the court's website.

But under U.K. law, any incoming justices need to take their judicial oath and oath of allegiance to the Queen in person before the president of the Supreme Court, currently Justice Robert Reed.

"The Supreme Court is making every effort to maintain a functioning court system in support of the administration of justice and rule of law during this challenging time," the court said in a statement on Tuesday's closed ceremony.

The ceremony took place in the library of the court building and was filmed on a smartphone. All the other justices attended "virtually" and the video recording is due to be posted online.

The event was vastly different from the swearing-in earlier this year of Justice Reed as president, replacing Justice Brenda Hale who retired in January. Judge Nicholas Hamlen was also promoted on the same day from the Court of Appeal to become a justice of the Supreme Court. They took their oaths before the other 10 justices, and the ceremony was attended by members of their family and government and judicial officials.

The top court said another, more standard swearing-in ceremony will be held for Justice Leggatt "when circumstances allow," during which he can renew the oaths he took on Tuesday in front of his family and friends as well as all the justices in person.

The swearing-in could not be postponed because Justice Leggatt's first Supreme Court case is scheduled to be heard Wednesday, marking the start of the new term. It centers on an insolvent electrical service company's claim for £300,000 in compensation. The question before the court is whether an adjudicator has jurisdiction to decide the dispute.

He will also be sitting on the panel to hear the highly-anticipated appeal by Mastercard in a case brought against the credit card company over the setting of interchange fees, which is due to be heard in May. The Supreme Court will, among other significant issues, weigh whether Walter Merricks, the former head of the U.K.'s Financial Ombudsman Service, can represent some 46.2 million British residents in the country's largest class action lawsuit.

The action is one of the first cases to be filed using the U.K.'s collective action regime, introduced by lawmakers in 2015 with the intention of giving consumers the chance to bring class action suits over anti-competitive practices. The Supreme Court's decision in the case will set a precedent for how claims will be certified in the future.

The suit itself is part of a series of battles between Mastercard and some of the U.K.'s biggest retailers and their customers over interchange fees, which are bank-to-bank charges imposed whenever shoppers pay using plastic.

Justice Leggatt was appointed to the Court of Appeal in 2018. Before becoming a High Court judge in 2012, he practiced as a barrister at Brick Court Chambers since 1985, specializing mainly in commercial cases. He became a QC in 1997. He is a graduate of King's College, Cambridge, and has also studied at Harvard University and the University of Chicago Law School.

--Additional reporting by Richard Crump. Editing by Janice Carter Brown.

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