Voters first approved $10 billion in bond money in 2008 for a project designed to shuttle riders between San Francisco and Los Angeles in less than three hours. It was slated to cost $33 billion and be finished by 2020. But the project has been beset by funding challenges, cost overruns and delays.

Now, state officials are focused on a 171-mile (275-kilometer) stretch connecting the Central Valley cities of Bakersfield and Merced, which is set to be operating by 2033. The entire San Francisco to Los Angeles line will now cost an estimated $106 billion to finish and officials hope to complete it in the next 20 years if there is money.

“I am directing my staff to review and determine whether the (California High-Speed Rail Authority) has followed through on the commitments it made to receive billions of dollars in federal funding. If not, I will have to consider whether that money could be given to deserving infrastructure projects elsewhere in the United States,” Transportation Secretary Sean Duffy said at a news conference in Los Angeles.

President Donald Trump canceled nearly $1 billion in federal funding for the high-speed rail project in 2019, during his first term. The Biden administration later restored the funding and, in December 2023, allocated $3.3 billion more.

Losing that money would be a major blow to the project. The rail authority’s most recent business plan counts on receiving up to $8 billion in federal money to help close a funding gap.

Ian Choudri, CEO of the California’s High-Speed Rail Authority, which oversees planning and funding for the project, said he welcomes the investigation.

“With multiple independent federal and state audits completed, every dollar is accounted for, and we stand by the progress and impact of this project,” Choudri said.

He said the project has created nearly 15,000 jobs and that more than 50 major structures have been completed so far.

Several Republican Congress members have taken aim at the project over its costs. On Thursday, Republican Rep. Kevin Kiley, who represents 3rd Congressional District that stretches alongside much of the state’s border with Nevada and includes Sacramento’s northeastern suburbs, called the California high-speed rail “the worst public infrastructure failure in U.S. history.”

“There is no plausible scenario where the cost to federal or state taxpayers can be justified. It is past time to stop throwing good money after bad, and we must formally end this project,” said Kiley, who introduced a bill earlier this year to make the project ineligible for further federal funding.

Kiley joined Duffy in Los Angeles’ Union Station for the announcement of the probe. Those present were interrupted at times by booing by about 30 demonstrators. The protesters also chanted “build the rail!” and held up signs that read “CA has no king” and “Don’t delay our train.”

Eli Lipmen, executive director of Move LA, an organization that advocates for efficient public transit systems, said the high-speed train project remains popular among many Californians.

“They said they’re going to start an investigation, but come on, this is a sham investigation,” Lipmen, who was at Union Station during the announcement, told KABC-TV.

Greg Regan and Shari Semelsberger, president and secretary-treasurer of the Transportation Trades Department coalition that includes all the country’s rail unions, said the project is the most ambitious and innovative transportation project in the country and urged Trump to become “a Builder-in-Chief by bringing high-speed rail to America.”

“Building ambitious projects requires bold leadership and a commitment to getting the job done. Just last year, President Trump complained that the United States does not have bullet trains similar to Japan. We agree with him that it is past time for our country to have these kinds of modern, efficient, high-capacity transportation systems,” they said in a statement.