According to a press release, the Livery Roundtable and the Black Car Assistance Corporation are suing to stop the pilot program on the grounds that the Taxi & Limousine Commission, which voted the program into existence in December, lacked authority to create the program without City Council approval.

"The Bloomberg Administration has once again chosen to impose its will without appropriate public input and with disregard for existing law,"  said BCAC Executive Director Ira J. Goldstein, in the press release. "From bike lanes to pedestrian plazas, too often so-called 'pilots' become permanent at the whim of City Hall."

In the months leading up to the TLC's December vote, the black car industry lobbied heavily against e-hailing, arguing that allowing yellow cabs to make prearranged pickups (as opposed to just street hails) would infringe on the livery business. The pilot program only passed after the TLC downgraded its e-hailing plan from permanent rule changes to a yearlong test case. The pilot program is slated to allow e-hailing apps for yellow cabs starting tomorrow.

In an emailed statement, the TLC said that it had yet to see a copy of the lawsuit, but that it expected the pilot program to hold up to legal scrutiny. TLC Commissioner David Yassky, meanwhile, was not pleased by the potential impediment.

“This suit seeks to keep the taxi industry and New Yorkers in the dark ages," Mr. Yassky said in an emailed statement. "Next thing, they’ll be suing restaurants to go back to wood-burning stoves.  Our rules allow for e-hail now, and the only question is, do we embrace these new services and ensure that consumer protections are in place, or listen to obstructionists and watch e-hail apps proliferate without any regulatory input.

The new lawsuit comes as several companies, including Uber, GetTaxi, Hailo and Flywheel, are preparing to launch on-demand taxi-hailing apps.

In the meantime, anyone planning to e-hail a yellow cab tomorrow may have to wait.

Update (5:26 p.m.): BCAC spokesman Bill Farrell told Betabeat that the state Supreme Court has scheduled a hearing on the lawsuit for February 28. According to Mr. Farrell, city representatives said during a preliminary hearing today that e-hailing apps won't be ready to launch until March 2.

Update (6:03): The New York City Law Department just emailed to indicate that there is no temporary restraining order preventing the city from launching its e-hailing pilot. "We're confident the pilot program will withstand court scrutiny," said Michelle Goldberg-Cahn, a lawyer for the city, in an emailed statement. "This program was approved in accordance with TLC rules and is completely proper."

You can read the lawsuit below:

(Photo: Yellow Cab NYC)

It's a secret point of pride for experienced New Yorkers that we know how to properly parse the mystifying taxi light system. It gives us a leg up over tourists, who spend so much time trying to differentiate between the Available and Off Duty lights that by the time they realize the cab is free, a local has already settled into the backseat.

But now, the Wall Street Journal reports that the Taxi & Limousine Commission has voted to revamp the baffling system: during scheduled taxi inspections between January and April, all taxis will be outfitted so that their signs only display one light when they're available. When they're taken or off-duty, the sign will be dark.

"From the point of view of the person on the street, they just need to know I can stick my hand up and flag it down," said TLC Commissioner David Yassky at the meeting, prior to the vote.

The TLC discussed the change during the same meeting in which they addressed Uber's longstanding e-hailing battle, though voting on that decision may be a long ways off. The TLC's Beaver Street office is still being run off of a generator after losing power during another large public meeting, during which attendees had to exit by walking down 19 flights of stairs.

Revamping the complicated light system should go a long way towards making a cab easier to catch. Mr. Yassky said the new system just makes "plain, common sense."

Still, some New Yorkers are rather disgruntled about the leveled playing field. "New York is not supposed to be easy," a certain Betabeat reporter angrily Skyped. "Tourists are supposed to get lost."

Additional reporting contributed by Nitasha Tiku.