We have long argued that tax breaks for development projects need to be dealt in a more conservative fashion. We need firm standards about the kinds of businesses that can have the breaks and the number of jobs they produce, and should stop assisting businesses that simply move from one town to the next within the same county. Any other approach is wasteful of county tax dollars, and we commend Erie County Executive Mark C. Poloncarz for his close attention to this problem.

But he and other critics are making a mistake in threatening to withhold incentives from a critical project already under way at the Buffalo Niagara Medical Campus. Conventus, a $100 million medical office, research and clinical facility, is designed as a link between the University at Buffalo Medical School and the planned John R. Oishei Children’s Hospital, successor to Women and Children’s Hospital on Bryant Street.

A vote on giving the project, by Ciminelli Real Estate, $4.24 million in tax breaks was unexpectedly delayed on Tuesday after it received only nine votes from directors of the Erie County Industrial Development Agency, one short of approval.

In addition to Poloncarz, objectors included Amherst Supervisor Barry Weinstein and Buffalo Urban League President Brenda McDuffie. Frank Mesiah, president of the Buffalo branch of the NAACP, abstained because of what he saw as insufficient information.

Poloncarz called the project a “glorified medical office,” which vastly undervalues its significance.

This project is a bright spot in Buffalo’s ongoing resurgence. It includes space for Kaleida Health, a University at Buffalo medical practice, retail establishments to support the medical campus and parking. Plans are also afoot for a medical research collaboration between UB and Moog, an East Aurora-based aerospace company that has a medical devices division.

Two problems are immediately obvious in this snag, which could yet be overcome at the ECIDA’s next board meeting in March. One is that the board should not change the rules midstream for anyone, let alone for a project of this size and importance to the county’s economic hopes.

But it is also odd that the project began without first having secured the tax breaks on which planners were relying. That’s the way developments have worked in Erie County, but it’s backward and it needs to change. As Poloncarz rightly observed, “It’s not an automatic green light. Any developer who automatically thinks they’re going to get tax incentives should reconsider. … They have to sell themselves. No one is entitled to receive tax breaks.”

He is right, and while that approach represents a refreshing change from the past, it is a change, nonetheless, and a significant one. The ECIDA board needs to be clear about its expectations and it needs to not change its rules after costs have been incurred based on past practices.

Beyond that, the IDA’s timing is terrible. Buffalo finally has some momentum going in developing assets that have gone unexplored for too long. Let’s not trip ourselves up now.