In her Jan. 21 column ("A new witch to chase in bridge collapse with hunt"), Katherine Kersten is dismissive of anyone questioning the early findings of the National Transportation Safety Board (NTSB). Kersten says, "Suddenly every critic seemed to have an engineering degree in his back pocket." While I do not carry my degree in my back pocket, I do proudly display it on my wall. I also happen to sit on the Joint Committee on the Bridge Collapse.

This is the bipartisan group representing both bodies of the Legislature that is investigating the actions and decisions leading up to and following the bridge collapse. While the scope of our investigation is different from that of the NTSB, which will determine the structural cause of the collapse, we must determine if at the state level there is anything we could've done differently or could change in the future to prevent such a disaster.

As a licensed professional engineer, I practiced engineering with a disciplined group of people. We have a code of conduct that discourages uniformed comment or conclusions outside our areas of expertise. Watch the media carefully and you will not see a professional engineer make conclusions on incomplete evidence.

The collapse was not an act of God; it was an error of oversight. Something was missed.

If there was an original design, specification or construction error that compromised safety, it was overlooked several times over 40 years. Lanes, roadway thickness and heavier medians were added, along with 33 percent more traffic, evidently without a verification of load capacity.

After the bridge fell into the river, I began reviewing the many years of bridge-inspection reports. I was surprised to see that problems were often reported for more than a decade without corrective action. There were instances in which the inspectors used exclamation points to draw attention to unaddressed problems. Other reports included many broken bolts and a tipped pier and "significant section loss." However, in its preliminary findings, the NTSB dismisses any factor related to the inspection, maintenance or condition of the bridge as a potential cause for collapse.

As an engineer, I find this unsettling and inappropriate. Does the NTSB not think that broken bolts are warning signs? Does it not think a tipped pier ought to be analyzed? Does it not think that "significant section loss" weakens gussets? Could not adding lanes, road thickness and heavier medians to underdesigned gussets be an error?

The NTSB does have a superb reputation when it comes to solving the causes of complex disasters. However, some of its recent actions are calling that reputation into question. The day after the bridge collapse, Gov. Tim Pawlenty hired the firm of Wiss, Janney, Elstner Associates (WJE) to conduct a "parallel" investigation. This firm is now working hand-in-hand with the NTSB, under a contract administered by MnDOT. However, WJE is also under obligation to represent MnDOT in any litigation stemming from the collapse -- a clear conflict of interest that undermines the work of the NTSB.

Mark Rosenker, the chairman of the NTSB, has also created credibility issues. He is not an engineer. He is a former Air Force general and has been a member of Dick Cheney's staff and a lobbyist. He has also been involved in several Republican presidential campaigns. His rush to pin the blame on a 40-year-old design problem, while ignoring all the other contributing factors, is unseemly at best. He also said that never in the history of his organization had it seen a similar underdesigning of gusset plates; yet in 1996, Ohio discovered gussets that were too thin on a sagging bridge. Since then, Ohio bridge inspectors have been inspecting gusset plate design, which Rosenker also stated inspectors are not trained to do.

Despite Kersten's objections, from an engineering perspective, some actions and statements of the NTSB warrant a degree of skepticism. I, along with the public, anxiously await the full findings of the report.

In the meantime, state senators and representatives will do their part in conducting a bipartisan investigation of the decisions that allowed this tragedy to occur.

Jim Carlson, DFL-Eagan, is a member of the Minnesota Senate.