Since the Interstate 35W bridge collapse, Minnesota has witnessed a witch hunt of the likes we've never seen before. Within days of the catastrophe on Aug. 1, 2007, a crowd of pundits and folks with a political ax to grind shouted for the heads of Tim Pawlenty, Carol Molnau, David Strom of the Taxpayers League of Minnesota and anyone who has ever opposed a gas tax increase.

Suddenly, every critic seemed to have an engineering degree in his back pocket. Accusations were made that Minnesota Department of Transportation inspections and maintenance were shoddy, irresponsible and done on the cheap.

Last week, the National Transportation Safety Board (NTSB) issued interim findings that should prompt the witch-hunt crowd to pack it in. (A final report is due within six months.) The "critical factor" in the collapse was a "serious design error" that dates from the bridge's construction in the mid-1960s, said NTSB chairman Mark Rosenker at a news conference.

"It is important to understand that bridge inspections would not have identified the error," Rosenker said. In fact, he said, the National Bridge Inspection Standards don't include procedures that would detect such a design flaw.

Unfortunately, the almost six-month public demonization of MnDOT -- launched before any findings were available -- has already taken a severe toll on the men and women who inspect and maintain our bridges.

For them, the toughest thing has been to see that some Minnesotans now question the bridge inspection team's dedication to the public welfare, said Dan Dorgan, state bridge engineer. "It's puzzling to us to be asked about other bridges, 'Is it safe?' Our neighbors, our kids, drive over these bridges. I guarantee that we would close a bridge if we thought it wasn't safe."

The bridge collapse and its media aftermath were "devastating for us," he said. "Everyone was turning inward, feeling the burden, asking, 'What might we have done that was wrong?'"

Supervisors and managers worked hard to "raise the spirits of inspectors and maintenance people, to reassure them 'we haven't lost faith in you' -- to try to keep people moving forward," he added.

And the NTSB's interim findings?

"For our inspectors, it's not a matter of jubilation but some sense of relief that this wasn't something that they missed. But it doesn't remove the sadness at the fact of the event," he said.

Can we agree that the witch-hunt phase of the tragedy is now over? Not so fast, say some DFLers and lawyers for collapse victims. They have a new witch: the NTSB itself. The agency's report "is not worth the paper it's printed on," Senate Transportation Committee Chairman Steve Murphy told the Pioneer Press last week.

That will be a hard sell. The NTSB is the gold standard in transportation disaster investigation, charged by Congress with unraveling not only every civil aviation accident but disasters such as the 1989 Exxon Valdez oil spill and bridge failures with national safety implications.

Who, then, does pass the Legislature's standards of impartiality? Why, lawyers, of course. A DFL-dominated legislative committee has hired the Minneapolis firm of Gray Plant Mooty to carry out its own investigation.

How impartial are these guys?

Gray Plant has an ongoing lawsuit on another matter against MnDOT -- the very agency whose actions the firm is now "investigating." Gray Plant also lobbies for the I-35W Solutions Alliance, a special-interest group that advocates "to improve the flow of people and materials in the I-35 corridor," according to Gray Plant lobbyist Robert Tennessen.

In other words, Gray Plant is trying to influence the Legislature on MnDOT's 35W-related projects at the same time it is investigating the agency's actions in relation to the bridge collapse.

Tennessen says that he is leaving the firm at the end of January. The Legislature's preliminary report on the bridge collapse is due out in March.

You can expect that the Legislature's law firm will find some heads to hand to the villain-hungry crowd. But someday the howls will die down, as lawyers and legislators turn their attention to another supposed scandal. Then the men and women who care for our bridges will finally be left to work in peace.

Katherine Kersten • Join the conversation at my blog, Think Again, which can be found at