IN A DISPLAY of just how petty public employee labor groups can be, Contra Costa unions are trying to block the county Board of Supervisors from obtaining data that would help them figure how to best trim their rapidly escalating pension costs.

Last week, I came to the defense of public employee unions' rights to collectively bargain, noting that it's our elected officials who approved unaffordable benefits. They are the ones in charge. I said that it's understandable that labor unions would advocate for the best deal for their members.

But that doesn't absolve organized labor from the burden to be responsible participants in the process. If government workers want to stave off growing anger about their benefits, they must stop their obstructionist behavior. Unfortunately, many unions, including some in Contra Costa, don't get it. They're throwing up disinformation and silly roadblocks that impede reasoned decision-making.

In the current Contra Costa case, county supervisors are preparing for negotiations with bargaining groups representing most of the roughly 8,500 full- and part-time unionized workers. The supervisors recognize that rising public employee pension costs must be brought under control. Among the options they might be considering are reduced benefits for new employees and higher pension contributions for some current workers.

There are many ways to reduce the benefits for future employees. The supervisors could, for example, alter retirement ages; change the salaries used in pension calculations from the highest year to, say, an average of the final three years; stop fattening those salaries with add-ons such as longevity pay, and car and uniform allowances; reduce the pension formulas applied to that salary; and lower cost-of-living adjustments.

To their credit, the supervisors and top county staff are trying to understand before they enter negotiations the financial effects of possible alternatives. So they submitted a request to the separately run Contra Costa County Employees' Retirement Association for actuarial data that will enable their experts to calculate the effect of possible changes. In short, county officials are behaving like responsible leaders.

But the retirement association -- run by the county treasurer, four representatives of workers and retirees, and four appointees of the county Board of Supervisors -- has an absurd procedure that requires the county to get the permission of the unions before it can get the data. Some of the unions have said no.

There are two issues here. First, the retirement board procedure is wrong. It's bad policy and it's legally unjustifiable. The information the county is seeking contains no privileged personal identifiers. It should be available to any party -- public employer, labor union or even member of the public -- that seeks it.

County officials are trying to understand their pension costs. The information should not be shrouded in secrecy. County officials should not be forced to jump through hoops to get it. They have been seeking the data for six weeks now. The retirement board on Wednesday will decide whether to release it despite union objections.

The other issue is the behavior of the unions. Barry Grove, head of the Deputy District Attorneys Association, Bob Britton, director for the union representing most management workers, and Suzie Griffith of AFSCME are insisting the county meet with them first to get their approval. The county has 20 different bargaining groups. Must each one sign off before county officials can proceed?

Think about it: The unions don't want the county to even have the data to intelligently understand the cost-consequences of possible options. They want elected officials to enter the negotiations with one hand tied behind their backs. They want them to bargain to get the information they need for bargaining.

It's the sort of behavior that fuels anti-union sentiment, that prompts people from all sides of the political aisle to question whether public employees should be allowed collective bargaining rights.

The message for unions is clear: Behave responsibly. Otherwise, the growing backlash in this state will explode. Your future is in your own hands.

Daniel Borenstein is a staff columnist and editorial writer. Reach him at 925-943-8248 or dborenstein@bayareanewsgroup.com.