Sometimes it seems as if the Spokane Transit Authority has traded its buses for rollercoasters. The up-and-down performance of the transit agency’s administration can make even its staunchest supporters feel queasy.

The latest dip was the news that the agency has failed to pay Social Security taxes for some employees for more than 20 years. The result could be a more than $1 million hit on the budget, depending on what kind of settlement STA can reach with the Social Security Administration. But the setback is more than financial for the agency that has long walked a public relations tightrope.

Ever since the passage of legislation that repealed the motor-vehicle-excise tax, STA has been at the mercy of taxpayers. In 2002, voters turned down a tax increase for STA, and the agency announced that dire cuts wouldn’t be immediately necessary after all. Despite that blow to credibility, voters overwhelming approved a sales tax increase to restore service in the spring of 2004. But that tax increase expires in 2008, so STA management must still show that it can be a trusted steward of public money.

That’s why the news about the missing Social Security payments is dispiriting. STA has adopted many business principles to deliver a service that was more efficient and responsive to public needs. The agency has chugged inexorably toward the goal of shoring up its credibility. But this accounting error has thrown up another public relations hurdle. It’s not insurmountable, but once again the agency needs to show that it is listening.

It can do that by lobbying the Legislature for a change in the 30-year-old law that says only elected officials can serve on municipal transit boards. The STA board could help its cause by telling lawmakers that it needs a rewrite of the law to allow the expertise of business leaders from the private sector. Such leaders are routinely tapped for the state Transportation Commission and higher education boards. It’s counterproductive to exclude them from agencies like the STA.

Granted, there appears to be nothing nefarious about the Social Security mishap. A Social Security administrator noted that laws governing transit agencies with their own pension systems can be confusing. But somebody should’ve caught this mistake. Perhaps somebody with a business background would have.

STA provides a valuable service, but public perception cannot be ignored. Most people do not take public transit, but most people pay for it. In any situation like that – whether it’s buses or other services for the needy – agencies must take great care to stay in the good graces of those who pay the bills.

In less than four years, STA must go back to the voters if it wants to extend the sales tax that has been so vital to improving service. The prospects for that will improve if the rollercoaster rides come to an end.