By Tim McLaughlin and Nate Raymond

BOSTON (Reuters) -The wife of Edward C. Johnson IV, whose family controls mutual fund powerhouse Fidelity Investments, has hired celebrity lawyer David Boies to represent her in a high-stakes divorce trial that opens on Friday.

Boies, 81, is the founder of law firm Boies Schiller Flexner LLP and represented Al Gore in the U.S. Supreme Court case over the 2000 presidential election recount. He told Reuters he will represent Allison Johnson in the divorce trial.

Judge Frances Giordano is presiding over the Johnson divorce, Boies said.

Johnson IV, whose personal fortune is estimated by Bloomberg at more than $6 billion, is expected to appear for opening statements inside a Lawrence, Massachusetts, courtroom for family and probate cases on Friday.

“It’s expected those (opening) statements will lay out the case in some detail,” Boies said in a telephone interview. “It’s a divorce case so it covers the basic issues of family law, including economic ones.”

Boies declined to provide any claims or details in the case, which has been impounded, a court order that shields it from public view.

Johnson IV and members of his legal team did not return messages seeking comment.

The divorce petition was filed more than a year ago but had not become public thus far.

Johnson IV is a director of FMR LLC, the parent company of Boston-based Fidelity. He is the youngest child of longtime Fidelity leader Edward “Ned” Johnson III, who died in March at age 91. Johnson IV’s sister, Abigail Johnson, is Fidelity’s chairman and chief executive.

As a director of FMR LLC, Johnson IV helps guide a family-controlled empire that generated $24 billion in revenue in 2021 and an operating profit of $8.1 billion.

The fortunes of his two sisters, Abigail and Elizabeth, are estimated at $21 billion and $6.5 billion, respectively.

Boies is well-known for representing the U.S. government in litigation against Microsoft Corp and for representing former Hollywood producer Harvey Weinstein, who was later convicted of sexual assault.

(Reporting by Tim McLaughlin and Nate Raymond in Boston Editing by Matthew Lewis)