Gov. Kathy Hochul of New York may believe she has the power to unilaterally shut down the nation’s first congestion pricing scheme, which was slated to pump $1 billion a year into the coffers of the nation’s largest transit system.

Not everyone thinks she’s right, and her opponents are eager to prove their case in court.

The New York City comptroller, Brad Lander, has assembled a collection of stakeholders to develop a legal strategy that would underpin one or more lawsuits seeking to get the central business district toll program back on track.

Mr. Lander is planning to outline the likely avenues of litigation at a news conference on Wednesday. The gathering underscores the swelling outrage among environmental and transportation advocates who have spent years persuading the government to enact tolls on drivers entering Manhattan’s core — only to see Ms. Hochul abruptly halt the plan less than a month before it was to go into effect.

Michael Gerrard, a prominent environmental lawyer at Columbia University, is spearheading the coalition’s legal strategy, alongside a New York University law professor, Roderick Hills, and Eric A. Goldstein, a senior attorney at the Natural Resources Defense Council.

Mr. Gerrard said the group believes Ms. Hochul may have violated a litany of laws, including the 2019 statute that the State Legislature passed and then-Gov. Andrew Cuomo signed saying that the Metropolitan Transportation Authority “shall” implement the congestion pricing program.

“It creates a mandatory duty, and it doesn’t give the governor the authority to cancel it,” he said. “We believe that the governor broke the law by putting an indefinite hold on congestion pricing.”