SAN FRANCISCO -- Uber's former chief executive, Travis Kalanick, has hired the former top federal prosecutor in San Francisco to represent him ahead of a deposition in a high-profile trade secrets case against Alphabet's (GOOGL.O) Waymo self-driving car unit, the attorney's firm said on Wednesday.

Melinda Haag, who served as U.S. attorney in Northern California under President Barack Obama, now practices white-collar defence law at the Orrick Herrington & Sutcliffe firm. She and a partner, Walter Brown, are representing Kalanick, Orrick spokesman Howard Mintz said.

Mintz declined to discuss the scope of Orrick's representation of Kalanick, who currently serves on Uber's board. A Kalanick representative could not immediately be reached for comment.

Kalanick is scheduled to be interviewed under oath by Waymo lawyers this week, Waymo attorney David Perlson said at a court hearing on Wednesday.

Waymo claimed in a lawsuit earlier this year that former engineer Anthony Levandowski downloaded more than 14,000 confidential files before leaving to set up a self-driving truck company, which Uber acquired soon after.

Uber denies it used any of Waymo's trade secrets. A trial is scheduled for October.

U.S. District Judge William Alsup, who is overseeing the case in San Francisco federal court, in May referred the matter to the U.S. Justice Department for possible criminal investigation of trade secret theft.

Kalanick co-founded the ride-sharing company Uber in 2009 and spread it around the world. He resigned as chief executive in June following a monthslong investigation prompted by allegations of sexual harassment at the company.