The effort to build a new terminal at Kansas City International Airport rumbled forward Thursday in ways that should infuriate voters who will decide the project’s fate.

Four firms have asked the city to consider their qualifications for the project. Initially, the city kept the identities of those firms secret.

That’s because the city now argues it should pick an airport terminal developer the same way it picks a cleaning service or security system. Under those procurement rules, members of the general public — indeed, the City Council itself — are typically barred from learning details of contracts until they’re signed.

In the case of the airport, a six-person committee that includes just two elected officials would review the proposals and pick one for submission to the full council.

Financial plans would remain secret. Design proposals — secret. Qualifications — secret. Questions and answers with proposers, now set for Aug. 14? Behind closed doors.

The details of the winning plan would be made public only after the city executes a memorandum of understanding with the successful proposer — an agreement that might be reached just weeks before a November election.

Some council members were furious Wednesday after learning they would be shut out of the process until it was almost over. On Thursday, they approved a resolution reasserting their right to attend meetings and screenings for project proposers.

Members of the council may have to sign non-disclosure agreements to do so. That still leaves the public on the outside looking in.

The secrecy surrounding this $1 billion deal is outrageous.

The terminal proposal is among the biggest public works projects in city history. It isn’t like buying paper towels for city buildings. Voters should have an opportunity to consider their options for design and financing a terminal before a company is picked.

Proposers are apparently worried some of their proprietary information could become public. That fear can be addressed by allowing disclosure of only non-proprietary information, including the names of the competitors, estimated costs, potential financial mechanisms, design parameters and the like.

Any proposing firm concerned about exposing those facts to public scrutiny should probably take its business elsewhere.

The state’s Sunshine Law doesn’t prohibit release of this information. And the city’s procurement process can be changed.

Secrecy is bad politics. Voters will never support a terminal plan drafted in the dark, nor should they.

On Thursday, we also learned the so-called private financing option for the terminal may largely be a fiction. Proposers, including Burns & McDonnell, may actually use third-party public bodies, such as the Port Authority or the Planned Industrial Expansion Authority, to borrow for the terminal.

The reason is obvious: Public financing is cheaper.

These important facts were discussed openly Thursday for the press and public to understand and judge. That’s why Kansas Citians must insist on a transparent process. It’s a shame we have to remind those involved in this project of a simple truth: The public’s business must be done in public.