Google made a handful of voluntary commitments to address other FTC concerns. The resolution was widely panned by advocates of stronger antitrust enforcement and continues to be cited as a top failure. Google's supporters say the FTC's light touch was appropriate and didn't burden the company as it continued to grow.

The Justice Department's current antitrust chief, Makan Delrahim, spent months negotiating with the FTC last year for jurisdiction to investigate Google this time around. He later recused himself in the case -- Google was briefly a client years before while he was in private practice -- as the department's top brass moved to take charge.

The lawsuit comes after internal tensions, with some department staffers questioning Attorney General William Barr's push to bring a case as quickly as possible, the Journal has reported. They worried the department hadn't yet built an airtight case and feared a rush to litigation could lead to a loss in court. They also worried Mr. Barr was driven by an interest in filing a case before the election. Other staff members were more comfortable moving ahead.

Mr. Barr has pushed the Justice Department to move ahead on the belief that antitrust enforcers have been too slow and hesitant to take action, according to a person familiar with his thinking. He has taken an unusually hands-on role in several areas of the department's work and repeatedly voiced interest in investigating tech-company dominance.

If the Microsoft case from 20 years ago is any guide, Mr. Barr's concern with speed could run up against the often slow pace of litigation.

After a circuitous route through the court system, including one initial trial-court ruling that ordered a breakup, Microsoft reached a 2002 settlement with the government and changed some aspects of its commercial behavior but stayed intact. It remained under court supervision and subject to terms of its consent decree with the government until 2011.

Antitrust experts have long debated whether the settlement was tough enough on Microsoft, though most observers believe the agreement opened up space for a new generation of competitors.

--Ryan Tracy and Sabrina Siddiqui contributed to this article.

Write to Brent Kendall at brent.kendall@wsj.com and Rob Copeland at rob.copeland@wsj.com

(END) Dow Jones Newswires

10-20-20 2023ET