US Chief Justice John Roberts was briefly hospitalised in June after falling and injuring his forehead, the Supreme Court said late on Tuesday.

The fall was likely the result of “light-headedness caused by dehydration”, with doctors having ruled out a seizure, according to a spokeswoman.

“The chief justice was treated at a local hospital on June 21 for an injury to his forehead sustained in a fall while walking for exercise near his home,” the statement said. “The injury required sutures, and out of an abundance of caution, he stayed in the hospital overnight and was discharged the next morning.”

The injury was reported earlier by the Washington Post, which said the incident occurred at the Chevy Chase Club in Maryland, where Roberts is a member.

Roberts, 65, suffered seizures in 2007 and 1993.

He was appointed in 2005 by Republican former President George W. Bush and is a traditional conservative, protective of the Supreme Court as an institution.

In his 2005 Senate confirmation hearing, Roberts compared the role of a judge to a baseball umpire calling balls and strikes. He has sought to portray himself as above politics.

He recently cemented his role as the Supreme Court’s dominant figure by siding with the four liberal justices in a trio of major rulings in June, including a 5-4 decision striking down a restrictive Louisiana abortion law.

Roberts is the justice closest to being a swing vote after the 2018 retirement of fellow conservative Anthony Kennedy. The court is closely divided, with five conservatives and four liberals.