By Jody Godoy

Feb 12 (Reuters) - President Donald Trump's pick to oversee the U.S. Department of Justice's blockbuster antitrust cases against Alphabet's GOOGL.O Google and Apple AAPL.O will have her commitment to enforcement tested by a Senate panel at her confirmation hearing on Wednesday.

Gail Slater, a veteran antitrust attorney and economic adviser to Vice President JD Vance, would lead the DOJ division that enforces laws against illegal monopolies and anticompetitive business behavior, if confirmed as assistant attorney general of the antitrust division.

Democrats on the committee are expected to press Slater for a commitment to enforcement and maintaining independence from the White House. In his first three weeks in office, Trump has overseen a transformation at the DOJ and Federal Bureau of Investigation that critics say threatens the agency's traditional independence from partisan politics.

Senator Cory Booker, a Democrat from New Jersey who is the ranking member on the Senate's antitrust committee, expressed concern ahead of the hearing about how efforts by Tesla TSLA.O CEO and Trump adviser Elon Musk to shrink the federal workforce would affect the antitrust division's work.

“Any efforts by Musk and Trump to fire or push out federal employees charged with enforcing our antitrust laws will hurt Americans at a time when families are struggling to make ends meet, pay their rents and mortgages, and buy groceries,” Booker said.

U.S. Senator Peter Welch, a Democrat from Vermont, will look for a commitment from Slater to continue the Biden administration's work on lowering prices in healthcare, agriculture and housing, a spokesperson said.

The DOJ's antitrust division and the Federal Trade Commission started cracking down on consolidation in the tech industry during Trump's first term, and continued under former President Joe Biden.

The DOJ sued Google for allegedly dominating online advertising technology markets, and won a landmark ruling in another case finding that Google holds an illegal monopoly in online search. Along with state attorneys general, the DOJ has also accused Apple, LiveNation LYV.N and Visa V.N of maintaining illegal monopolies.

Senator Amy Klobuchar, a Democrat from Minnesota who previously led the Senate antitrust subcommittee, said she would be asking Slater "about how she intends to independently and consistently enforce the antitrust laws to promote competition, lower costs, and protect consumers."

She added: "That includes continuing the cases the Antitrust Division is currently litigating, blocking anticompetitive mergers, and stopping price fixing that raises prices."

U.S. Senator Mike Lee, a Utah Republican who leads the antitrust subcommittee, said in a statement that Slater will "successfully lead the Antitrust Division in defending American consumers and continue President Trump's first administration work to rein in Big Tech monopolies."

Slater has worked at Fox Corp FOXA.O and Roku ROKU.O, and represented Big Tech companies at a now-defunct trade group called the Internet Association. She began her career at law firm Freshfields Bruckhaus Deringer and spent 10 years at the FTC.

(Reporting by Jody Godoy in New YorkEditing by Matthew Lewis)

((Jody.Godoy@thomsonreuters.com;))