Alito, 76, is one of six conservative justices on the nine-person Supreme Court

The Supreme Court’s 6-3 conservative lean wouldn’t change if Alito retired and Trump nominated a new justice. But Alito’s retirement would allow Trump to appoint a fourth justice to the court. Alito was nominated by then-President George W. Bush in the fall of 2005 and took his seat on the bench in January 2006.

Trump has lashed out at the Supreme Court for several rulings against him on controversial issues like his sweeping tariff policy and his challenge to birthright citizenship. Alito sided with Trump on those two issues.

The timing of a Supreme Court justice’s retirement is crucial because the party in power can change the court’s political leaning for decades.