The debacle involving Caltrans' lax bridge inspections didn't take place on Gov. Jerry Brown's watch. But Caltrans' response is happening during his administration.

So far, that response has been defensive, arrogant, dismissive and not the least bit reassuring.

On Tuesday, the California Senate is scheduled to open hearings into the issue of Caltrans inspections. Lawmakers need to drill down into the most immediate question – the integrity of the Bay Bridge. But they also need to delve into the lax disciplinary procedures within Caltrans that The Bee's Charles Piller has revealed.

As Piller reported last Sunday, bridge inspector Duane Wiles failed to verify the accuracy of his testing equipment, falsified some data and discarded information that could have been used to reconstruct his work on parts of various bridges he inspected.

Wiles' direct supervisor, Brian Liebich, knew about Wiles' problems but failed to do the obvious – launch a no-holds-barred investigation into Wiles' work to ensure that all suspect structures were examined and, if needed, repaired.

So that raises a question: Why does Caltrans permit an employee who is caught falsifying inspection data to keep his job for two years?

Senate Transportation Committee Chair Mark DeSaulnier of Concord has asked that numerous Caltrans witnesses testify before the committee. They include acting Caltrans Director Malcolm Dougherty.

Supervisors in Wiles' chain of command also need to explain themselves. Additionally, Caltrans needs to make available engineers identified in The Bee's report last Sunday who raised questions internally about the inspections.

Bay Area transportation commissioners certainly weren't buying Caltrans' assurances, and neither should the Legislature.

The Metropolitan Transportation Commission last week quizzed Tony Anziano, the Caltrans official who oversees toll bridges, including the Bay Bridge, about why he didn't know about inspection problems at the bridge until The Bee reported on them. That came after he all but shrugged off concerns, saying that in the worst-case scenario, an investigation would show "we are in good shape."

Something is wrong with the culture of Caltrans when a high-level official dismisses safety concerns. Lawmakers need to determine how this culture grew and festered.

Contrition by Caltrans might be too much to expect. But Caltrans has no excuse for failing to produce information and witnesses sought by legislators. If Brown's department fails to answer legitimate questions, the governor also will have some explaining to do.

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