The US Supreme Court could be entering a new era of partisanship, under Republican control.

Brett Kavanaugh has been sworn in as a judge, after senators received an FBI report clearing him of allegations of sexual assault.

More than 2500 legal scholars have written to Donald Trump with concerns about Kavanaugh's selection.

One of them, UCLA's Richard Abel, told Mike Yardley there were many Republican judges more qualified for the role.

"There are literally thousands of people who have equivalent records. The nomination itself is simply an attempt to pack the court with Republicans who would vote the party line."

He said Kavanaugh's testimony to the Senate Judiciary Committee suggested he wasn't prepared to become a Supreme Court judge.

"He has to separate his personal feelings from his judicial actions and his behaviour on the stand suggests he could not do so."

LISTEN ABOVE AS RICHARD ABEL SPEAKS WITH MIKE YARDLEY